# Changes: Prisoners dilemma game

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The Prisoner's Dilemma constitutes a problem in game theory. It was originally framed by Merrill Flood and Melvin Dresher working at RAND in 1950. Albert W. Tucker formalized the game with prison sentence payoffs and gave it the "Prisoner's Dilemma" name (Poundstone, 1992).

In its "classical" form, the prisoner's dilemma (PD) is presented as follows:

Two suspects are arrested by the police. The police have insufficient evidence for a conviction, and, having separated both prisoners, visit each of them to offer the same deal. If one testifies ("defects") for the prosecution against the other and the other remains silent, the betrayer goes free and the silent accomplice receives the full 10-year sentence. If both remain silent, both prisoners are sentenced to only six months in jail for a minor charge. If each betrays the other, each receives a five-year sentence. Each prisoner must choose to betray the other or to remain silent. Each one is assured that the other would not know about the betrayal before the end of the investigation. How should the prisoners act?

If we assume that each player prefers shorter sentences to longer ones, and that each gets no utility out of lowering the other player's sentence, and that there are no reputation effects from a player's decision, then the prisoner's dilemma forms a non-zero-sum game in which two players may each "cooperate" with or "defect" from (i.e., betray) the other player. In this game, as in all game theory, the only concern of each individual player ("prisoner") is maximizing his/her own payoff, without any concern for the other player's payoff. The unique equilibrium for this game is a Pareto-suboptimal solution—that is, rational choice leads the two players to both play defect even though each player's individual reward would be greater if they both played cooperatively.

In the classic form of this game, cooperating is strictly dominated by defecting, so that the only possible equilibrium for the game is for all players to defect. In simpler terms, no matter what the other player does, one player will always gain a greater payoff by playing defect. Since in any situation playing defect is more beneficial than cooperating, all rational players will play defect, all things being equal.

In the iterated prisoner's dilemma the game is played repeatedly. Thus each player has an opportunity to "punish" the other player for previous non-cooperative play. Cooperation may then arise as an equilibrium outcome. The incentive to defect is overcome by the threat of punishment, leading to the possibility of a cooperative outcome. So if the game is infinitely repeated, cooperation may be a subgame perfect Nash equilibrium although both players defecting always remains an equilibrium and there are many other equilibrium outcomes.

In casual usage, the label "prisoner's dilemma" may be applied to situations not strictly matching the formal criteria of the classic or iterative games; for instance, those in which two entities could gain important benefits from cooperating or suffer from the failure to do so, but find it merely difficult or expensive, not necessarily impossible, to coordinate their activities to achieve cooperation.

## Strategy for the classical prisoner's dilemmaEdit

The classical prisoner's dilemma can be summarized thus:

Prisoner B Stays Silent Prisoner B Betrays
Prisoner A Stays Silent Each serves 6 months Prisoner A: 10 years
Prisoner B: goes free
Prisoner A Betrays Prisoner A: goes free
Prisoner B: 10 years
Each serves 5 years

In this game, regardless of what the opponent chooses, each player always receives a higher payoff (lesser sentence) by betraying; that is to say that betraying is the strictly dominant strategy. For instance, Prisoner A can accurately say, "No matter what Prisoner B does, I personally am better off betraying than staying silent. Therefore, for my own sake, I should betray." However, if the other player acts similarly, then they both betray and both get a lower payoff than they would get by staying silent. Rational self-interested decisions result in each prisoner's being worse off than if each chose to lessen the sentence of the accomplice at the cost of staying a little longer in jail himself. Hence a seeming dilemma. In game theory, this demonstrates very elegantly that in a non-zero sum game a Nash Equilibrium need not be a Pareto optimum.

## Generalized formEdit

We can expose the skeleton of the game by stripping it of the prisoner framing device. The generalized form of the game has been used frequently in experimental economics. The following rules give a typical realization of the game.

There are two players and a banker. Each player holds a set of two cards: one printed with the word "Cooperate", the other printed with "Defect" (the standard terminology for the game). Each player puts one card face-down in front of the banker. By laying them face down, the possibility of a player knowing the other player's selection in advance is eliminated (although revealing one's move does not affect the dominance analysis[1]). At the end of the turn, the banker turns over both cards and gives out the payments accordingly.

If player 1 (red) defects and player 2 (blue) cooperates, player 1 gets the Temptation to Defect payoff of 5 points while player 2 receives the Sucker's payoff of 0 points. If both cooperate they get the Reward for Mutual Cooperation payoff of 3 points each, while if they both defect they get the Punishment for Mutual Defection payoff of 1 point. The checker board payoff matrix showing the payoffs is given below.

Cooperate Defect 3, 3 0, 5 5, 0 1, 1

In "win-lose" terminology the table looks like this:

Cooperate Defect win-win lose much-win much win much-lose much lose-lose

These point assignments are given arbitrarily for illustration. It is possible to generalize them, as follows:

Cooperate Defect R, R S, T T, S P, P

Where T stands for Temptation to defect, R for Reward for mutual cooperation, P for Punishment for mutual defection and S for Sucker's payoff. To be defined as Prisoner's dilemma, the following inequalities must hold:

T > R > P > S

This condition ensures that the equilibrium outcome is defection, but that cooperation Pareto dominates equilibrium play. In addition to the above condition, if the game is repeatedly played by two players, the following condition should be added.[2]

2 R > T + S

If that condition does not hold, then full cooperation is not necessarily Pareto optimal, as the players are collectively better off by having each player alternate between cooperate and defect.

These rules were established by cognitive scientist Douglas Hofstadter and form the formal canonical description of a typical game of Prisoner's Dilemma.

A simple special case occurs when the advantage of defection over cooperation is independent of what the co-player does and cost of the co-players defection is independent of one's own action, i.e. T+S = P+R.

## Human behavior in the Prisoner's DilemmaEdit

One experiment based on the simple dilemma found that approximately 40% of participants played "cooperate" (i.e., stayed silent).[3]

## The iterated prisoner's dilemmaEdit

If two players play Prisoner's Dilemma more than once in succession, having memory of at least one previous game, it is called iterated Prisoner's Dilemma. Amongst results shown by Nobel Prize winner Robert Aumann in his 1959 paper, rational players repeatedly interacting for indefinitely long games can sustain the cooperative outcome. Popular interest in the iterated prisoners dilemma (IPD) was kindled by Robert Axelrod in his book The Evolution of Cooperation (1984). In this he reports on a tournament he organized in which participants have to choose their mutual strategy again and again, and have memory of their previous encounters. Axelrod invited academic colleagues all over the world to devise computer strategies to compete in an IPD tournament. The programs that were entered varied widely in algorithmic complexity, initial hostility, capacity for forgiveness, and so forth.

Axelrod discovered that when these encounters were repeated over a long period of time with many players, each with different strategies, greedy strategies tended to do very poorly in the long run while more altruistic strategies did better, as judged purely by self-interest. He used this to show a possible mechanism for the evolution of altruistic behaviour from mechanisms that are initially purely selfish, by natural selection.

The best deterministic strategy was found to be "Tit for Tat," which Anatol Rapoport developed and entered into the tournament. It was the simplest of any program entered, containing only four lines of BASIC, and won the contest. The strategy is simply to cooperate on the first iteration of the game; after that, the player does what his opponent did on the previous move. Depending on the situation, a slightly better strategy can be "Tit for Tat with forgiveness." When the opponent defects, on the next move, the player sometimes cooperates anyway, with a small probability (around 1%-5%). This allows for occasional recovery from getting trapped in a cycle of defections. The exact probability depends on the line-up of opponents.

By analysing the top-scoring strategies, Axelrod stated several conditions necessary for a strategy to be successful.

Nice
The most important condition is that the strategy must be "nice", that is, it will not defect before its opponent does (this is sometimes referred to as an "optimistic" algorithm). Almost all of the top-scoring strategies were nice; therefore a purely selfish strategy will not "cheat" on its opponent, for purely utilitarian reasons first.
Retaliating
However, Axelrod contended, the successful strategy must not be a blind optimist. It must sometimes retaliate. An example of a non-retaliating strategy is Always Cooperate. This is a very bad choice, as "nasty" strategies will ruthlessly exploit such players.
Forgiving
Successful strategies must also be forgiving. Though players will retaliate, they will once again fall back to cooperating if the opponent does not continue to play defects. This stops long runs of revenge and counter-revenge, maximizing points.
Non-envious
The last quality is being non-envious, that is not striving to score more than the opponent (impossible for a ‘nice’ strategy, i.e., a 'nice' strategy can never score more than the opponent).

Therefore, Axelrod reached the oxymoron-sounding conclusion that selfish individuals for their own selfish good will tend to be nice and forgiving and non-envious.

The optimal (points-maximizing) strategy for the one-time PD game is simply defection; as explained above, this is true whatever the composition of opponents may be. However, in the iterated-PD game the optimal strategy depends upon the strategies of likely opponents, and how they will react to defections and cooperations. For example, consider a population where everyone defects every time, except for a single individual following the Tit-for-Tat strategy. That individual is at a slight disadvantage because of the loss on the first turn. In such a population, the optimal strategy for that individual is to defect every time. In a population with a certain percentage of always-defectors and the rest being Tit-for-Tat players, the optimal strategy for an individual depends on the percentage, and on the length of the game.

A strategy called Pavlov (an example of Win-Stay, Lose-Switch) cooperates at the first iteration and whenever the player and co-player did the same thing at the previous iteration; Pavlov defects when the player and co-player did different things at the previous iteration. For a certain range of parameters, Pavlov beats all other strategies by giving preferential treatment to co-players which resemble Pavlov.

Deriving the optimal strategy is generally done in two ways:

1. Bayesian Nash Equilibrium: If the statistical distribution of opposing strategies can be determined (e.g. 50% tit-for-tat, 50% always cooperate) an optimal counter-strategy can be derived analytically.[4]
2. Monte Carlo simulations of populations have been made, where individuals with low scores die off, and those with high scores reproduce (a genetic algorithm for finding an optimal strategy). The mix of algorithms in the final population generally depends on the mix in the initial population. The introduction of mutation (random variation during reproduction) lessens the dependency on the initial population; empirical experiments with such systems tend to produce Tit-for-Tat players (see for instance Chess 1988), but there is no analytic proof that this will always occur.

Although Tit-for-Tat is considered to be the most robust basic strategy, a team from Southampton University in England (led by Professor Nicholas Jennings [2] and consisting of Rajdeep Dash, Sarvapali Ramchurn, Alex Rogers, Perukrishnen Vytelingum) introduced a new strategy at the 20th-anniversary Iterated Prisoner's Dilemma competition, which proved to be more successful than Tit-for-Tat. This strategy relied on cooperation between programs to achieve the highest number of points for a single program. The University submitted 60 programs to the competition, which were designed to recognize each other through a series of five to ten moves at the start. Once this recognition was made, one program would always cooperate and the other would always defect, assuring the maximum number of points for the defector. If the program realized that it was playing a non-Southampton player, it would continuously defect in an attempt to minimize the score of the competing program. As a result,[5] this strategy ended up taking the top three positions in the competition, as well as a number of positions towards the bottom.

This strategy takes advantage of the fact that multiple entries were allowed in this particular competition, and that the performance of a team was measured by that of the highest-scoring player (meaning that the use of self-sacrificing players was a form of minmaxing). In a competition where one has control of only a single player, Tit-for-Tat is certainly a better strategy. Because of this new rule, this competition also has little theoretical significance when analysing single agent strategies as compared to Axelrod's seminal tournament. However, it provided the framework for analysing how to achieve cooperative strategies in multi-agent frameworks, especially in the presence of noise. In fact, long before this new-rules tournament was played, Richard Dawkins in his book The Selfish Gene pointed out the possibility of such strategies winning if multiple entries were allowed, but remarked that most probably Axelrod would not have allowed them if they had been submitted. It also relies on circumventing rules about the prisoner's dilemma in that there is no communication allowed between the two players. When the Southampton programs engage in an opening "ten move dance" to recognize one another, this only reinforces just how valuable communication can be in shifting the balance of the game.

If an iterated PD is going to be iterated exactly N times, for some known constant N, then it is always game theoretically optimal to defect in all rounds. The only possible Nash equilibrium is to always defect. The proof goes like this: one might as well defect on the last turn, since the opponent will not have a chance to punish the player. Therefore, both will defect on the last turn. Thus, the player might as well defect on the second-to-last turn, since the opponent will defect on the last no matter what is done, and so on. For cooperation to emerge between game theoretic rational players, the total number of rounds must be random, or at least unknown to the players. However, even in this case always defect is no longer a strictly dominant strategy, only a Nash equilibrium. The superrational strategy in this case is to cooperate against a superrational opponent, and in the limit of large fixed N, experimental results on strategies agree with the superrational version, not the game-theoretic rational one.

Another odd case is "play forever" prisoner's dilemma. The game is repeated infinitely many times, and the player's score is the average (suitably computed).

The prisoner's dilemma game is fundamental to certain theories of human cooperation and trust. On the assumption that the PD can model transactions between two people requiring trust, cooperative behaviour in populations may be modelled by a multi-player, iterated, version of the game. It has, consequently, fascinated many scholars over the years. In 1975, Grofman and Pool estimated the count of scholarly articles devoted to it at over 2,000. The iterated prisoner's dilemma has also been referred to as the "Peace-War game".[6]

### Continuous Iterated Prisoner's DilemmaEdit

Most work on the iterated prisoner's dilemma has focused on the discrete case, in which players either cooperate or defect, because this model is relatively simple to analyze. However, some researchers have looked at models of the continuous iterated prisoner's dilemma, in which players are able to make a variable contribution to the other player. Le and Boyd[7] found that in such situations, cooperation is much harder to evolve than in the discrete iterated prisoner's dilemma. The basic intuition for this result is straigh­tforward: in a continuous prisoner's dilemma, if a population starts off in a non-cooperative equilibrium, players who are only marginally more cooperative than non-cooperators get little benefit from assorting with one another. By contrast, in a discrete prisoner's dilemma, Tit-for-Tat cooperators get a big payoff boost from assorting with one another in a non-cooperative equilibrium, relative to non-cooperators. Since Nature arguably offers more opportunities for variable cooperation rather than a strict dichotomy of cooperation or defection, the continuous prisoner's dilemma may help explain why real-life examples of Tit-for-Tat-like cooperation are extremely rare in Nature (ex. Hammerstein[8]) even though Tit-for-Tat seems robust in theoretical models.

### Learning psychology and game theoryEdit

Where game players can learn to estimate the likelihood of other players defecting, their own behaviour is influenced by their experience of the others' behaviour. Simple statistics show that inexperienced players are more likely to have had, overall, atypically good or bad interactions with other players. If they act on the basis of these experiences (by defecting or cooperating more than they would otherwise) they are likely to suffer in future transactions. As more experience is accrued a truer impression of the likelihood of defection is gained and game playing becomes more successful. The early transactions experienced by immature players are likely to have a greater effect on their future playing than would such transactions affect mature players. This principle goes part way towards explaining why the formative experiences of young people are so influential and why, for example, those who are particularly vulnerable to bullying sometimes become bullies themselves.

The likelihood of defection in a population may be reduced by the experience of cooperation in earlier games allowing trust to build up.[9] Hence self-sacrificing behaviour may, in some instances, strengthen the moral fibre of a group. If the group is small the positive behaviour is more likely to feed back in a mutually affirming way, encouraging individuals within that group to continue to cooperate. This is allied to the twin dilemma of encouraging those people whom one would aid to indulge in behaviour that might put them at risk. Such processes are major concerns within the study of reciprocal altruism, group selection, kin selection and moral philosophy.

Douglas Hofstadter in his Metamagical Themas proposed that the definition of "rational" that led "rational" players to defect is faulty. He proposed that there is another type of rational behavior, which he called "superrational", where players take into account that the other person is presumably superrational, like them. Superrational players behave identically, and know that they will behave identically. They take that into account before they maximize their payoffs, and they therefore cooperate.

This view of the one-shot PD leads to cooperation as follows:

• Any superrational strategy will be the same for both superrational players, since both players will think of it.
• therefore the superrational answer will lie on the diagonal of the payoff matrix
• when you maximize return from solutions on the diagonal, you cooperate

However, if a superrational player plays against a rational opponent, he will serve a 10-year sentence, and the rational player will go free.

One-shot cooperation is observed in human culture, wherever religious and ethical codes exist.

Superrationality is not studied by academics, as rationality excludes any superrational behavior.

### MoralityEdit

While it is sometimes thought that morality must involve the constraint of self-interest, David Gauthier famously argues that co-operating in the prisoners dilemma on moral principles is consistent with self-interest and the axioms of game theory.[How to reference and link to summary or text] In his opinion, it is most prudent to give up straigh­tforward maximizing and instead adopt a disposition of constrained maximization, according to which one resolves to cooperate in the belief that the opponent will respond with the same choice, while in the classical PD it is explicitly stipulated that the response of the opponent does not depend on the player's choice. This form of contractarianism claims that good moral thinking is just an elevated and subtly strategic version of basic means-end reasoning.

Douglas Hofstadter expresses a strong personal belief that the mathematical symmetry is reinforced by a moral symmetry, along the lines of the Kantian categorical imperative: defecting in the hope that the other player cooperates is morally indefensible.[How to reference and link to summary or text] If players treat each other as they would treat themselves, then they will cooperate.

## Real-life examplesEdit

These particular examples, involving prisoners and bag switching and so forth, may seem contrived, but there are in fact many examples in human interaction as well as interactions in nature that have the same payoff matrix. The prisoner's dilemma is therefore of interest to the social sciences such as economics, politics and sociology, as well as to the biological sciences such as ethology and evolutionary biology. Many natural processes have been abstracted into models in which living beings are engaged in endless games of Prisoner's Dilemma (PD). This wide applicability of the PD gives the game its substantial importance.

### In politicsEdit

In political science, for instance, the PD scenario is often used to illustrate the problem of two states engaged in an arms race. Both will reason that they have two options, either to increase military expenditure or to make an agreement to reduce weapons. Neither state can be certain that the other one will keep to such an agreement; therefore, they both incline towards military expansion. The paradox is that both states are acting rationally, but producing an apparently irrational result. This could be considered a corollary to deterrence theory.

### In scienceEdit

In sociology or criminology, the PD may be applied to an actual dilemma facing two inmates. The game theorist Marek Kaminski, a former political prisoner, analysed the factors contributing to payoffs in the game set up by a prosecutor for arrested defendants (cf. References). He concluded that while the PD is the ideal game of a prosecutor, numerous factors may strongly affect the payoffs and potentially change the properties of the game.

In environmental studies, the PD is evident in crises such as global climate change. All countries will benefit from a stable climate, but any single country is often hesitant to curb [[Carbon dioxide|Template:Co2]] emissions. The benefit to an individual country to maintain current behavior is greater than the benefit to all countries if behavior was changed, therefore explaining the current impasse concerning climate change.[10]

In program management and technology development, the PD applies to the relationship between the customer and the developer. Capt Dan Ward, an officer in the US Air Force, examined The Program Manager's Dilemma in an article published in Defense AT&L, a defense technology journal.[11]

### In sportsEdit

PD frequently occurs in cycling races, for instance in the Tour de France. Consider two cyclists halfway in a race, with the peloton (larger group) at great distance behind them. The two riders often work together (mutual cooperation) by sharing the tough load of the front position, where there is no shelter from the wind. If neither of the riders makes an effort to stay ahead, the peloton will soon catch up (mutual defection). An often-seen scenario is one rider doing the hard work alone (cooperating), keeping the two ahead of the peloton. Nearer to the finish (where the threat of the peloton has disappeared), the game becomes a simple zero-sum game, with each rider trying to avoid at all costs giving a slipstream advantage to the other rider. If there was a (single) defecting rider in the preceding prisoners' dilemma, it is usually he who will win this zero-sum game, having saved energy in the cooperating rider's slipstream. The cooperating rider's attitude may seem extremely naive, but he often has no other choice when both riders have different physical profiles. The cooperating rider typically has an endurance profile, whereas the defecting rider will more likely be a sprinter. When continuously taking the head position of the twosome, the 'cooperating' rider is merely trying to ride away from the defecting sprinter using his endurance advantage over long distance, thus avoiding a sprint duel at the finish, which he would be bound to lose, even if the sprinting rider had cooperated. Just after the escape from the peloton, the endurance-sprinter difference is less of importance, and it is therefore at this stage of the race that mutual cooperation PD can usually be observed. Arguably, it is this almost unavoidable presence of PD (and its transition in zero-sum games) that (unconsciously) makes cycling an exciting sport to watch.

PD hardly applies to running sports, because of the negligible importance of air resistance (and shelter from it).

In high school wrestling, sometimes participants intentionally lose unnaturally large amounts of weight so as to compete against lighter opponents. In doing so, the participants are clearly not at their top level of physical and athletic fitness and yet often end up competing against the same opponents anyway, who have also followed this practice (mutual defection). The result is a reduction in the level of competition. Yet if a participant maintains their natural weight (cooperating), they will most likely compete against a stronger opponent who has lost considerable weight.

### In economicsEdit

Without enforceable agreements, members of a cartel are also involved in a (multi-player) prisoners' dilemma.[12] 'Cooperating' typically means keeping prices at a pre-agreed minimum level. 'Defecting' means selling under this minimum level, instantly stealing business (and profits) from other cartel members. Ironically, anti-trust authorities want potential cartel members to mutually defect, ensuring the lowest possible prices for consumers.

### In lawEdit

The theoretical conclusion of PD is one reason why, in many countries, plea bargaining is forbidden. Often, precisely the PD scenario applies: it is in the interest of both suspects to confess and testify against the other prisoner/suspect, even if each is innocent of the alleged crime. Arguably, the worst case is when only one party is guilty — here, the innocent one is unlikely to confess, while the guilty one is likely to confess and testify against the innocent.

### In the mediaEdit

In the 2008 edition of Big Brother (UK), the dilemma was applied to two of the housemates. A prize fund of £50,000 was available. If housemates chose to share the prize fund, each would receive £25,000. If one chose to share, and the other chose to take, the one who took it would receive the entire £50,000. If both chose to take, both housemates would receive nothing. The housemates had a minute to discuss their decision, and were given the possibility to lie. Both housemates declared they would share the prize fund, but either could have potentially been lying. When asked to give their final answers by big brother, both housemates did indeed choose to share, and so won £25,000 each.

### Multiplayer dilemmasEdit

Many real-life dilemmas involve multiple players. Although metaphorical, Hardin's tragedy of the commons may be viewed as an example of a multi-player generalization of the PD: Each villager makes a choice for personal gain or restraint. The collective reward for unanimous (or even frequent) defection is very low payoffs (representing the destruction of the "commons"). Such multi-player PDs are not formal as they can always be decomposed into a set of classical two-player games. The commons are not always exploited: William Poundstone, in a book about the Prisoner's Dilemma (see References below), describes a situation in New Zealand where newspaper boxes are left unlocked. It is possible for someone to take a paper without paying (defecting) but very few do, feeling that if they do not pay then neither will others, destroying the system.

Because there is no mechanism for personal choice to influence others' decisions, this type of thinking relies on correlations between behavior, not on causation. Because of this property, those who do not understand superrationality often mistake it for magical thinking. Without superrationality, not only petty theft, but voluntary voting requires widespread magical thinking, since a non-voter is a free rider on a democratic system.

## Related gamesEdit

### Closed-bag exchangeEdit

Hofstadter[13] once suggested that people often find problems such as the PD problem easier to understand when it is illustrated in the form of a simple game, or trade-off. One of several examples he used was "closed bag exchange":

Two people meet and exchange closed bags, with the understanding that one of them contains money, and the other contains a purchase. Either player can choose to honour the deal by putting into his bag what he agreed, or he can defect by handing over an empty bag.

In this game, defection is always the best course, implying that rational agents will never play. However, in this case both players cooperating and both players defecting actually give the same result, so chances of mutual cooperation, even in repeated games, are few.

### Friend or Foe?Edit

Friend or Foe? is a game show that aired from 2002 to 2005 on the Game Show Network in the United States. It is an example of the prisoner's dilemma game tested by real people, but in an artificial setting. On the game show, three pairs of people compete. As each pair is eliminated, they play a game of Prisoner's Dilemma to determine how their winnings are split. If they both cooperate (Friend), they share the winnings 50-50. If one cooperates and the other defects (Foe), the defector gets all the winnings and the cooperator gets nothing. If both defect, both leave with nothing. Notice that the payoff matrix is slightly different from the standard one given above, as the payouts for the "both defect" and the "cooperate while the opponent defects" cases are identical. This makes the "both defect" case a weak equilibrium, compared with being a strict equilibrium in the standard prisoner's dilemma. If you know your opponent is going to vote Foe, then your choice does not affect your winnings. In a certain sense, Friend or Foe has a payoff model between "Prisoner's Dilemma" and "Chicken".

The payoff matrix is

Cooperate Defect 1, 1 0, 2 2, 0 0, 0

This payoff matrix was later used on the British television programmes Shafted and Golden Balls.

## NotesEdit

1. A simple "tell" that partially or wholly reveals one player's choice — such as the Red player playing their Cooperate card face-up — does not change the fact that Defect is the dominant strategy. When one is considering the game itself, communication has no effect whatsoever. However, when the game is being played in real life considerations outside of the game itself may cause communication to matter. It is a point of utmost importance to the full implications of the dilemma that when we do not need to take into account external considerations, single-instance Prisoner's Dilemma is not affected in any way by communications. Even in single-instance Prisoner's Dilemma, meaningful prior communication about issues external to the game could alter the play environment, by raising the possibility of enforceable side contracts or credible threats. For example, if the Red player plays their Cooperate card face-up and simultaneously reveals a binding commitment to blow the jail up if and only if Blue Defects (with additional payoff -11,-10), then Blue's Cooperation becomes dominant. As a result, players are screened from each other and prevented from communicating outside of the game.
2. Dawkins, Richard (1989). The Selfish Gene, Oxford University Press. ISBN 0-19-286092-5. Page: 204 of Paperback edition
3. Tversky, Amos (2004). Preference, Belief, and Similarity: Selected Writings, MIT Press.
4. For example see the 2003 study “Bayesian Nash equilibrium; a statistical test of the hypothesis” for discussion of the concept and whether it can apply in real economic or strategic situations (from Tel Aviv University).
5. The 2004 Prisoner's Dilemma Tournament Results show University of Southampton's strategies in the first three places, despite having fewer wins and many more losses than the GRIM strategy. (Note that in a PD tournament, the aim of the game is not to “win” matches — that can easily be achieved by frequent defection). It should also be pointed out that even without implicit collusion between software strategies (exploited by the Southampton team) tit-for-tat is not always the absolute winner of any given tournament; it would be more precise to say that its long run results over a series of tournaments outperform its rivals. (In any one event a given strategy can be slightly better adjusted to the competition than tit-for-tat, but tit-for-tat is more robust). The same applies for the tit-for-tat-with-forgiveness variant, and other optimal strategies: on any given day they might not 'win' against a specific mix of counter-strategies.An alternative way of putting it is using the Darinian ESS simulation. In such a simulation Tit-for-Tat will almost always come to dominate, though nasty strategies will drift in and out of the population because a Tit-for-Tat population is penetratable by non-retaliating nice strategies which in turn are easy prey for the nasty strategies. Richard Dawkins showed that here no static mix of strategies form a stable equilibrium and the system will always oscillate between bounds.
6. Shy, O., 1996, Industrial Organization: Theory and Applications, Cambridge, Mass.: The MIT Press.
7. Le, S. and R. Boyd (2007) "Evolutionary Dynamics of the Continuous Iterated Prisoner's Dilemma" Journal of Theoretical Biology, Volume 245, 258–267.
8. Hammerstein, P. (2003). Why is reciprocity so rare in social animals? A protestant appeal. In: P. Hammerstein, Editor, Genetic and Cultural Evolution of Cooperation, MIT Press. pp. 83–94.
9. 9.0 9.1 This argument for the development of cooperation through trust is given in The Wisdom of Crowds , where it is argued that long-distance capitalism was able to form around a nucleus of Quakers, who always dealt honourably with their business partners. (Rather than defecting and reneging on promises — a phenomenon that had discouraged earlier long-term unenforceable overseas contracts). It is argued that dealings with reliable merchants allowed the meme for cooperation to spread to other traders, who spread it further until a high degree of cooperation became a profitable strategy in general commerce
10. The Economist (2007) [1].
11. Ward, D. (2004) The Program Manager's Dilemma The Program Manager's Dilemma (Defense AT&L, Defense Acquisition University Press).
12. Nicholson, Walter (2000), Intermediate Microeconomics (8th ed.), Harcourt
13. Hofstadter, Douglas R. (1985). Metamagical Themas: questing for the essence of mind and pattern, Bantam Dell Pub Group. ISBN 0-465-04566-9. - see Ch.29 The Prisoner's Dilemma Computer Tournaments and the Evolution of Cooperation.

## ReferencesEdit

1. REDIRECT Template:Refbegin
• Robert Aumann, “Acceptable points in general cooperative n-person games”, in R. D. Luce and A. W. Tucker (eds.), Contributions to the Theory 23 of Games IV, Annals of Mathematics Study 40, 287–324, Princeton University Press, Princeton NJ.
• Axelrod, R. (1984). The Evolution of Cooperation. ISBN 0-465-02121-2
• Bicchieri, Cristina (1993). Rationality and Coordination. Cambridge University Press
• Kenneth Binmore, Fun and Games.
• David M. Chess (1988). Simulating the evolution of behavior: the iterated prisoners' dilemma problem. Complex Systems, 2:663–670.
• Dresher, M. (1961). The Mathematics of Games of Strategy: Theory and Applications Prentice-Hall, Englewood Cliffs, NJ.
• Flood, M.M. (1952). Some experimental games. Research memorandum RM-789. RAND Corporation, Santa Monica, CA.
• Kaminski, Marek M. (2004) Games Prisoners Play Princeton University Press. ISBN 0-691-11721-7 http://webfiles.uci.edu/mkaminsk/www/book.html
• Poundstone, W. (1992) Prisoner's Dilemma Doubleday, NY NY.
• Greif, A. (2006). Institutions and the Path to the Modern Economy: Lessons from Medieval Trade. Cambridge University Press, Cambridge, UK.
• Rapoport, Anatol and Albert M. Chammah (1965). Prisoner's Dilemma. University of Michigan Press.
• S. Le and R. Boyd (2007) "Evolutionary Dynamics of the Continuous Iterated Prisoner's Dilemma" Journal of Theoretical Biology, Volume 245, 258–267. Full text
• A. Rogers, R. K. Dash, S. D. Ramchurn, P. Vytelingum and N. R. Jennings (2007) “Coordinating team players within a noisy iterated Prisoner’s Dilemma tournament” Theoretical Computer Science 377 (1-3) 243-259. [3]
1. redirect Template:Refend

### BooksEdit

• Banfield, G., & Christodoulou, C. (2005). Can Self-Control Be Explained Through Games? River Edge, NJ: World Scientific Publishing Co.
• Bendor, J., Kramer, R. M., & Stout, S. (2005). When in Doubt... Cooperation in a Noisy Prisoner's Dilemma. Northampton, MA: Edward Elgar Publishing.
• Bicchieri, Cristina and Mitchell Green (1997) "Symmetry Arguments for Cooperation in the Prisoner's Dilemma", in G. Holmstrom-Hintikka and R. Tuomela (eds.), Contemporary Action Theory: The Philosophy and Logic of Social Action, Kluwer.
• Goren, H., & Bornstein, G. (1999). Reciprocation and learning in the Intergroup Prisoner's Dilemma Game. Mahwah, NJ: Lawrence Erlbaum Associates Publishers.
• Insko, C. A., & Schopler, J. (1998). Differential distrust of groups and individuals. Mahwah, NJ: Lawrence Erlbaum Associates Publishers.
• Komorita, S. S., & Parks, C. D. (1999). Reciprocity and cooperation in social dilemmas: Review and future directions. Mahwah, NJ: Lawrence Erlbaum Associates Publishers.
• Larsen, J. D. (2002). Prisoner's dilemma as a model for understanding decisions. Mahwah, NJ: Lawrence Erlbaum Associates Publishers.
• Liebrand, W. B. G., & Messick, D. M. (1999). Dynamic and static theories of costs and benefits of cooperation. Mahwah, NJ: Lawrence Erlbaum Associates Publishers.
• McCabe, K. A., & Smith, V. L. (2001). Goodwill Accounting and the process of exchange. Cambridge, MA: The MIT Press.
• Schulz, U. (1994). Mathematical models of gaming behavior. Lisse, Netherlands: Swets & Zeitlinger Publishers.

### PapersEdit

Aaftink, J. (1989). Far-sighted equilibria in 2x2, non-cooperative, repeated games: Theory and Decision Vol 27(3) Nov 1989, 175-192.

• Acevedo, M., & Krueger, J. I. (2005). Evidential reasoning in the prisoner's dilemma: American Journal of Psychology Vol 118(3) Fal 2005, 431-457.
• Ajzen, I. (1971). Attitudinal vs. normative messages: An investigation of the differential effects of persuasive communications on behavior: Sociometry Vol 34(2) Jun 1971, 263-280.
• Alvard, M. S., & Nolin, D. A. (2002). Rousseau's whale hunt? Coordination among big-game hunters: Current Anthropology Vol 43(4) Aug-Oct 2002, 533-559.
• Antonides, G. (1994). Mental accounting in a sequential Prisoner's Dilemma game: Journal of Economic Psychology Vol 15(2) Jun 1994, 351-374.
• Arce M, D. G. (1994). Stability criteria for social norms with applications to the prisoner's dilemma: Journal of Conflict Resolution Vol 38(4) Dec 1994, 749-765.
• Aretz, H.-J. (2005). The Relevance of Value Commitments in the Supply of Public Goods: Zeitschrift fur Soziologie Vol 34(5) Oct 2005, 326-343.
• Arfi, B. (2006). Linguistic Fuzzy-Logic Social Game of Cooperation: Rationality and Society Vol 18(4) Nov 2006, 471-537.
• Armstrong, S., & Roback, H. (1977). An empirical test of Schutz' three-dimensional theory of group process in adolescent dyads: Small Group Behavior Vol 8(4) Nov 1977, 443-456.
• Arribas, I., & Urbano, A. (2005). Repeated games with probabilistic horizon: Mathematical Social Sciences Vol 50(1) Jul 2005, 39-60.
• Ashmore, T. M. (1987). The Prisoner's Dilemma: A computer adaptation: Western Journal of Speech Communication Vol 51(1) Win 1987, 117-126.
• Au, W. T., & Komorita, S. S. (2002). Effects of initial choices in the prisoner's dilemma: Journal of Behavioral Decision Making Vol 15(4) Oct 2002, 343-359.
• Axelrod, R. (1980). More effective choice in the Prisoner's Dilemma: Journal of Conflict Resolution Vol 24(3) Sep 1980, 379-403.
• Axelrod, R. (1990). The emergence of cooperation among egoists. New York, NY: Cambridge University Press.
• Axelrod, R., & Dion, D. (1988). The further evolution of cooperation: Science Vol 242(4884) Dec 1988, 1385-1390.
• Axelrod, R., & Hamilton, W. D. (1981). The evolution of cooperation: Science Vol 211(4489) Mar 1981, 1390-1396.
• Axelrod, R., Riolo, R. L., & Cohen, M. D. (2002). Beyond geography: Cooperation with persistent links in the absence of clustered neighborhoods: Personality and Social Psychology Review Vol 6(4) 2002, 341-346.
• Baker, F., & Rachlin, H. (2001). Probability of reciprocation in repeated prisoner's dilemma games: Journal of Behavioral Decision Making Vol 14(1) Jan 2001, 51-67.
• Baker, F., & Rachlin, H. (2002). Self-control by pigeons in the prisoner's dilemma: Psychonomic Bulletin & Review Vol 9(3) Sep 2002, 482-488.
• Bartholdi, J. J., Butler, C. A., & Trick, M. A. (1986). More on the evolution of cooperation: Journal of Conflict Resolution Vol 30(1) Mar 1986, 129-140.
• Basu, K. (1977). Information and strategy in iterated Prisoner's Dilemma: Theory and Decision Vol 8(3) Jul 1977, 293-298.
• Batson, C. D., & Ahmad, N. (2001). Empathy-induced altruism in a prisoner's dilemma II: What if the target of empathy has defected? : European Journal of Social Psychology Vol 31(1) Jan-Feb 2001, 25-36.
• Batson, C. D., & Moran, T. (1999). Empathy-induced altruism in a prisoner's dilemma: European Journal of Social Psychology Vol 29(7) Nov 1999, 909-924.
• Bauer, N., & Krivohlavy, J. (1974). Co-operative conflict resolution in institutionalized boy dyads: Journal of Child Psychology and Psychiatry Vol 15(1) Jan 1974, 13-21.
• Becker, N. C., & Cudd, A. E. (1990). Indefinitely repeated games: A response to Carroll: Theory and Decision Vol 28(2) Mar 1990, 189-195.
• Bedell, J., & Sistrunk, F. (1973). Power, opportunity costs, and sex in a mixed-motive game: Journal of Personality and Social Psychology Vol 25(2) Feb 1973, 219-226.
• Behr, R. L. (1981). Nice guys finish last--sometimes: Journal of Conflict Resolution Vol 25(2) Jun 1981, 289-300.
• Bendor, J. (1993). Uncertainty and the evolution of cooperation: Journal of Conflict Resolution Vol 37(4) Dec 1993, 709-734.
• Bendor, J., Kramer, R., & Swistak, P. (1996). Cooperation under uncertainty: What is new, what is true and what is important: Comment: American Sociological Review Vol 61(2) Apr 1996, 333-338.
• Bendor, J., Kramer, R. M., & Stout, S. (1991). When in doubt...: Cooperation in a noisy prisoner's dilemma: Journal of Conflict Resolution Vol 35(4) Dec 1991, 691-719.
• Bethlehem, D. W. (1973). Cooperation, competition and altruism among school children in Zambia: International Journal of Psychology Vol 8(2) 1973, 125-135.
• Betz, B. (1991). Response to strategy and communication in an arms race-disarmament dilemma: Journal of Conflict Resolution Vol 35(4) Dec 1991, 678-690.
• Betz, B. (1995). Comparison of GRIT versus GRIT/Tit-For-Tat: Psychological Reports Vol 76(1) Feb 1995, 322.
• Bisin, A., Topa, G., & Verdier, T. (2004). Cooperation as a transmitted cultural trait: Rationality and Society Vol 16(4) Nov 2004, 477-507.
• Bixenstine, V. E., & Douglas, J. (1967). Effect of psychopathology of group consensus and cooperative choice in a six-person game: Journal of Personality and Social Psychology Vol 5(1) Jan 1967, 32-37.
• Bohnet, I., & Kubler, D. (2005). Compensating the cooperators: Is sorting in the prisoner's dilemma possible? : Journal of Economic Behavior & Organization Vol 56(1) Jan 2005, 61-76.
• Bolle, F., & Ockenfels, P. (1990). Prisoners' Dilemma as a game with incomplete information: Journal of Economic Psychology Vol 11(1) Mar 1990, 69-84.
• Bonacich, P. (1972). Norms and cohesion as adaptive responses to potential conflict: An experimental study: Sociometry Vol 35(3) Sep 1972, 357-375.
• Bonacich, P. (1976). Secrecy and solidarity: Sociometry Vol 39(3) Sep 1976, 200-208.
• Bonacich, P., Shure, G. H., Kahan, J. P., & Meeker, R. J. (1976). Cooperation and group size in the N-person Prisoner's Dilemma: Journal of Conflict Resolution Vol 20(4) Dec 1976, 687-706.
• Boone, C., De Brabander, B., Carree, M., de Jong, G., van Olffen, W., & van Witteloostuijn, A. (2002). Locus of control and learning to cooperate in a prisoner's dilemma game: Personality and Individual Differences Vol 32(5) Apr 2002, 929-946.
• Boone, C., De Brabander, B., & van Witteloostuijn, A. (1999). The impact of personality on behavior in five Prisoner's Dilemma games: Journal of Economic Psychology Vol 20(3) Jun 1999, 343-377.
• Boone, C., De Brabander, B., & van Witteloostuijn, A. (1999). Locus of control and strategic behaviour in a prisoner's dilemma game: Personality and Individual Differences Vol 27(4) Oct 1999, 695-706.
• Boone, R. T., & Macy, M. W. (1999). Unlocking the doors of the Prisoner's Dilemma: Dependence, selectivity, and cooperation: Social Psychology Quarterly Vol 62(1) Mar 1999, 32-52.
• Bornstein, G. (2004). Cooperation in Intergroup Social Dilemmas. New York, NY: Cambridge University Press.
• Bornstein, G., Erev, I., & Goren, H. (1994). The effect of repeated play in the IPG and IPD team games: Journal of Conflict Resolution Vol 38(4) Dec 1994, 690-707.
• Boyd, R. (1988). Is the repeated prisoner's dilemma a good model of reciprocal altruism? : Ethology & Sociobiology Vol 9(2-4) Jul 1988, 211-222.
• Boyd, R., & Lorberbaum, J. P. (1987). No pure strategy is evolutionarily stable in the repeated Prisoner's Dilemma game: Nature Vol 327(6117) May 1987, 58-59.
• Brams, S. J. (1975). Newcomb's problem and Prisoner's Dilemma: Journal of Conflict Resolution Vol 19(4) Dec 1975, 596-612.
• Brams, S. J., & Hessel, M. P. (1983). Staying power in sequential games: Theory and Decision Vol 15(3) Sep 1983, 279-302.
• Braver, S. L., & Barnett, B. (1976). Effects of modeling on cooperation in a Prisoner's Dilemma game: Journal of Personality and Social Psychology Vol 33(2) Feb 1976, 161-169.
• Braver, S. L., & Rohrer, V. (1975). When martyrdom pays: The effects of information concerning the opponents' past game behavior: Journal of Conflict Resolution Vol 19(4) Dec 1975, 652-662.
• Brew, J. S. (1973). An altruism parameter for Prisoner's Dilemma: Journal of Conflict Resolution Vol 17(2) Jun 1973, 351-367.
• Brosig, J. (2002). Identifying cooperative behavior: Some experimental results in a prisoner's dilemma game: Journal of Economic Behavior & Organization Vol 47(3) Mar 2002, 275-290.
• Bruins, J. J., Liebrand, W. B., & Wilke, H. A. (1989). About the saliency of fear and greed in social dilemmas: European Journal of Social Psychology Vol 19(2) Mar-Apr 1989, 155-161.
• Budescu, D. V., Rapoport, A., & Suleiman, R. (1995). Common pool resource dilemmas under uncertainty: Qualitative test of equilibrium solutions: Games and Economic Behavior Vol 10(1) Jul 1995, 171-201.
• Busch, M. L., & Reinhardt, E. R. (1993). Nice strategies in a world of relative gains: The problem of cooperation under anarchy: Journal of Conflict Resolution Vol 37(3) Sep 1993, 427-445.
• Buskens, V., & Snijders, C. (1997). "Individual heuristics and the dynamics of cooperation in large groups": Additional results using analytical methods: Psychological Review Vol 104(4) Oct 1997, 792-800.
• Butterworth, R. L. (1977). Relative acceptability: A proposed strategy for the bargaining game: Theory and Decision Vol 8(4) Oct 1977, 337-350.
• Cable, D. M., & Shane, S. (1997). A prisoner's dilemma approach to entrepreneur-venture capitalist relationships: Academy of Management Review Vol 22(1) Jan 1997, 142-176.
• Cabon-Dhersin, M.-L., & Ramani, S. V. (2007). Opportunism, trust and cooperation: A game theoretic approach with heterogeneous agents: Rationality and Society Vol 19(2) May 2007, 203-228.
• Caldwell, M. D. (1976). Communication and sex effects in a five-person Prisoner's Dilemma Game: Journal of Personality and Social Psychology Vol 33(3) Mar 1976, 273-280.
• Camac, C. (1992). Information preferences in a two-person social dilemma. Elmsford, NY: Pergamon Press.
• Carroll, J. W. (1987). Indefinite terminating points and the iterated Prisoner's Dilemma: Theory and Decision Vol 22(3) May 1987, 247-256.
• Carroll, J. W. (2000). The backward induction argument: Theory and Decision Vol 48(1) Feb 2000, 61-84.
• Cassar, A. (2007). Coordination and cooperation in local, random and small world networks: Experimental evidence: Games and Economic Behavior Vol 58(2) Feb 2007, 209-230.
• Charness, G., Frechette, G. R., & Qin, C.-Z. (2007). Endogenous transfers in the prisoner's dilemma game: An experimental test of cooperation and coordination: Games and Economic Behavior Vol 60(2) Aug 2007, 287-306.
• Chaudhuri, A., Sopher, B., & Strand, P. (2002). Cooperation in social dilemmas, trust and reciprocity: Journal of Economic Psychology Vol 23(2) Apr 2002, 231-250.
• Chertkoff, J. M. (1992). Do Psychologists Care Whether People Behave as Game Theory Prescribes? : PsycCRITIQUES Vol 37 (10), Oct, 1992.
• Choi, J.-K. (2007). Trembles may support cooperation in a repeated prisoner's dilemma game: Journal of Economic Behavior & Organization Vol 63(3) Jul 2007, 384-393.
• Clements, K. C., & Stephens, D. W. (1995). Testing models of non-kin cooperation: Mutualism and the Prisoner's Dilemma: Animal Behaviour Vol 50(2) Aug 1995, 527-535.
• Cohen, M. D., Riolo, R. L., & Axelrod, R. (2001). The role of social structure in the maintenance of cooperative regimes: Rationality and Society Vol 13(1) Feb 2001, 5-32.
• Collins, F. L. (1977). Effects of repression-sensitization on response latency in a Prisoner's Dilemma game: Psychological Reports Vol 41(1) Aug 1977, 202.
• Coombs, C. H. (1973). A reparameterization of the Prisoner's Dilemma game: Behavioral Science Vol 18(6) Nov 1973, 424-428.
• Cooper, R., DeJong, D. V., Forsythe, R., & Ross, T. W. (1996). Cooperation without Reputation: Experimental Evidence from Prisoner's Dilemma Games: Games and Economic Behavior Vol 12(2) Feb 1996, 187-218.
• Corfman, K. P., & Lehmann, D. R. (1994). The prisoner's dilemma and the role of information in setting advertising budgets: Journal of Advertising Vol 23(2) Jun 1994, 35-48.
• Cox, S. J., Sluckin, T. J., & Steele, J. (1999). Group size, memory, and interaction rate in the evolution of cooperation: Current Anthropology Vol 40(3) Jun 1999, 369-377.
• Dawes, R. M. (1980). Social dilemmas: Annual Review of Psychology Vol 31 1980, 169-193.
• De Herdt, T. (2003). Cooperation and Fairness: The Flood-Dresher Experiment Revisited: Review of Social Economy Vol 61(2) Jun 2003, 183-210.
• De Jong, P. J., Peters, M., De Cremer, D., & Vranken, C. (2002). Blushing after a moral transgression in a prisoner's dilemma game: Appeasing or revealing? : European Journal of Social Psychology Vol 32(5) Sep-Oct 2002, 627-644.
• Dera, M., Revenstorf, D., Heyse, H., & Fitting, U. (1977). An experimental game as a diagnostic aid: Zeitschrift fur Klinische Psychologie Vol 6(3) 1977, 161-176.
• Downing, L. L. (1975). The Prisoner's Dilemma game as a problem-solving phenomenon: An outcome maximization interpretation: Simulation & Games Vol 6(4) Dec 1975, 366-391.
• Downing, L. L., & Ritter, E. H. (1976). Effects of contingencies on cooperative responding in a prisoner's dilemma game with anticipated shock outcomes: Personality and Social Psychology Bulletin Vol 2(1) Win 1976, 51-54.
• Dwyer, P. D., & Minnegal, M. (1997). Sago games: Cooperation and change among Sago producers of Papua New Guinea: Evolution and Human Behavior Vol 18(2) Mar 1997, 89-108.
• Eisenberger, R., Cotterell, N., & Marvel, J. (1987). Reciprocation ideology: Journal of Personality and Social Psychology Vol 53(4) Oct 1987, 743-750.
• Eiser, J. R., & Bhavnani, K.-K. (1974). The effect of situational meaning on the behaviour of subjects in the Prisoner's Dilemma Game: European Journal of Social Psychology Vol 4(1) 1974, 93-97.
• Engelmann, W. (1994). Conditions for disarmament: A game theoretical model: Group Decision and Negotiation Vol 3(3) Sep 1994, 321-332.
• Erev, I., & Roth, A. E. (2001). Simple reinforcement learning models and reciprocation in the prisoner's dilemma game. Cambridge, MA: The MIT Press.
• Evens, T. M. (1985). The paradox of Nuer feud and the leopard-skin chief: A "creative" solution to the prisoner's dilemma: American Ethnologist Vol 12(1) Feb 1985, 84-102.
• Fader, P. S., & Hauser, J. R. (1988). Implicit coalitions in a generalized Prisoner's Dilemma: Journal of Conflict Resolution Vol 32(3) Sep 1988, 553-582.
• Fantino, E., Gaitan, S. C., Meyer, S., & Stolarz-Fantino, S. (2006). Self-Control in a Prisoner's Dilemma Game: The Role of Trial Spacing and an Interfering Task: Journal of Behavioral Decision Making Vol 19(3) Jul 2006, 273-284.
• Feeley, T. H., Tutzauer, F., Rosenfeld, H. L., & Young, M. J. (1997). Cooperation in an infinite-choice continuous-time prisoner's dilemma: Simulation & Gaming Vol 28(4) Dec 1997, 442-459.
• Ferguson, E. D., & Schmitt, S. (1988). Gender-linked stereotypes and motivation affect performance in the Prisoner's Dilemma Game: Perceptual and Motor Skills Vol 66(3) Jun 1988, 703-714.
• Fischer, I., & Suleiman, R. (1997). Election frequency and the emergence of cooperation in a simulated intergroup conflict: Journal of Conflict Resolution Vol 41(4) Aug 1997, 483-508.
• Forst, B., & Lucianovic, J. (1977). The prisoner's dilemma: Theory and reality: Journal of Criminal Justice Vol 5(1) Spr 1977, 55-64.
• Fox, J., & Guyer, M. (1978). Public choice and cooperation in n-person Prisoner's Dilemma: Journal of Conflict Resolution Vol 22(3) Sep 1978, 469-481.
• Frank, R. H., Gilovich, T., & Regan, D. T. (1993). The evolution of one-shot cooperation: An experiment: Ethology & Sociobiology Vol 14(4) Jul 1993, 247-256.
• Friedland, N. (1990). Attribution of control as a determinant of cooperation in exchange interactions: Journal of Applied Social Psychology Vol 20(4, Pt 1) Mar 1990, 303-320.
• Frohlich, N., & Oppenheimer, J. (1996). When is universal contribution best for the group? Characterizing optimality in the prisoners' dilemma: Journal of Conflict Resolution Vol 40(3) Sep 1996, 502-516.
• Fujiki, C., & Dickinson, J. (1987). Using the genetic algorithm to generate LISP source code to solve the prisoner's dilemma. Hillsdale, NJ, England: Lawrence Erlbaum Associates, Inc.
• Furnham, A., & Quilley, R. (1989). The Protestant work ethic and the Prisoner's Dilemma Game: British Journal of Social Psychology Vol 28(1) Mar 1989, 79-87.
• Gardin, H., Kaplan, K. J., Firestone, I. J., & Cowan, G. A. (1973). Proxemic effects on cooperation, attitude, and approach-avoidance in a Prisoner's Dilemma game: Journal of Personality and Social Psychology Vol 27(1) Jul 1973, 13-18.
• Gardner, R. M., Corbin, T. L., Beltramo, J. S., & Nickell, G. S. (1984). The prisoner's dilemma game and cooperation in the rat: Psychological Reports Vol 55(3) Dec 1984, 687-696.
• Garner, K., & Deutsch, M. (1974). Cooperative behavior in dyads: Effects of dissimilar goal orientations and differing expectations about the partner: Journal of Conflict Resolution Vol 18(4) Dec 1974, 634-645.
• Goehring, D. J., & Kahan, J. P. (1976). The uniform N -person Prisoner's Dilemma game: Journal of Conflict Resolution Vol 20(1) Mar 1976, 111-128.
• Goetze, D. (1994). Comparing prisoner's dilemma, commons dilemma, and public goods provision designs in laboratory experiments: Journal of Conflict Resolution Vol 38(1) Mar 1994, 56-86.
• Gomez, I., Gonzalez, J. M., & Cardona, T. (1976). Relationship between cooperation in the Prisoner's Dilemma game and the E (Extraversion), N (Neuroticism) and P (Psychoticism) scales: Revista Latinoamericana de Psicologia Vol 8(1) 1976, 25-29.
• Goren, H. (2001). The effect of out-group competition on individual behavior and out-group perception in the Intergroup Prisoner's Dilemma (IPD) game: Group Processes & Intergroup Relations Vol 4(2) Apr 2001, 160-182.
• Goren, H., & Bornstein, G. (2000). The effects of intragroup communication on intergroup cooperation in the repeated Intergroup Prisoner's Dilemma (IPD) game: Journal of Conflict Resolution Vol 44(5) Oct 2000, 700-719.
• Grandberg, D., Stevens, J. S., & Katz, S. (1975). Effect of communication on cooperation in expanded Prisoner's Dilemma and Chicken games: Simulation & Games Vol 6(2) Jun 1975, 166-187.
• Green, L., Price, P. C., & Hamburger, M. E. (1995). Prisoner's dilemma and the pigeon: Control by immediate consequences: Journal of the Experimental Analysis of Behavior Vol 64(1) Jul 1995, 1-17.
• Grim, P. (1997). The undecidability of the spatialized prisoner's dilemma: Theory and Decision Vol 42(1) Jan 1997, 53-80.
• Groes, E., Jacobsen, H. J., Sloth, B., & Tranaes, T. (1998). Nash equilibrium with lower probabilities: Theory and Decision Vol 44(1) Jan 1998, 37-66.
• Grossman, P. Z. (1994). The dilemma of prisoners: Choice during Stalin's great terror, 1936-38: Journal of Conflict Resolution Vol 38(1) Mar 1994, 43-55.
• Guth, W., Kliemt, H., & Ockenfels, A. (2003). Fairness versus efficiency: An experimental study of (mutual) gift giving: Journal of Economic Behavior & Organization Vol 50(4) Apr 2003, 465-475.
• Guyer, M., Fox, J., & Hamburger, H. (1973). Format effects in the Prisoner's Dilemma game: Journal of Conflict Resolution Vol 17(4) Dec 1973, 719-744.
• Hall, S. S. (2003). Transitions between cooperative and non-cooperative responding in the "pigeon's dilemma": Behavioural Processes Vol 60(3) Jan 2003, 199-208.
• Hama, Y. (1980). The effect of goal setting on cooperative responding in social interaction using the PD game: Japanese Journal of Experimental Social Psychology Vol 19(2) Feb 1980, 137-145.
• Hamburger, H. (1973). N-person Prisoner's Dilemma: Journal of Mathematical Sociology Vol 3(1) 1973, 27-48.
• Handy, C. (1996). The Pound Sterling5 auction. Thousand Oaks, CA ; Maidenhead, BRK, England: Sage Publications, Inc; Open University Press.
• Hardin, R. (2003). Gaming trust. New York, NY: Russell Sage Foundation.
• Harrington, J. E., Jr. (1995). Cooperation in a One-Shot Prisoners' Dilemma: Games and Economic Behavior Vol 8(2) 1995, 364-377.
• Harris, A. C., & Madden, G. J. (2002). Delay discounting and performance on the prisoner's dilemma game: Psychological Record Vol 52(4) Fal 2002, 429-440.
• Hartman, E. A. (1974). Degree of cooperation in a prisoner's dilemma as a function of sex roles, responsiveness, and the exploitativeness of the simulated other: Personality and Social Psychology Bulletin Vol 1(1) 1974, 287-289.
• Hartman, E. A. (1980). Motivational bases of sex differences in choice behavior: Journal of Conflict Resolution Vol 24(3) Sep 1980, 455-475.
• Hashimoto, H. (1987). Beliefs and choice behavior at Prisoner's Dilemma Game: Journal of Human Development Vol 23 Jan 1987, 48-52.
• Hauert, C., & Doebell, M. (2004). Spatial structure often inhibits the evolution of cooperation in the snowdrift game: Nature Vol 428(6983) Apr 2004, 643-646.
• Hauk, E. (2003). Multiple Prisoner's Dilemmma games with(out) an outside option: An experimental study: Theory and Decision Vol 54(3) May 2003, 207-229.
• Hauk, E., & Nagel, R. (2001). Choice of partners in multiple two-person prisoner's dilemma games: An experimental study: Journal of Conflict Resolution Vol 45(6) Dec 2001, 770-793.
• Hayashi, N. (1995). Emergence of cooperation in one-shot prisoner's dilemmas and the role of trust: Japanese Journal of Psychology Vol 66(3) Aug 1995, 184-190.
• Heckathorn, D. D. (1988). Collective sanctions and the creation of prisoner's dilemma norms: American Journal of Sociology Vol 94(3) Nov 1988, 535-562.
• Hoffman, R. (1999). The independent localisations of interaction and learning in the repeated prisoner's dilemma: Theory and Decision Vol 47(1) Aug 1999, 57-72.
• Hoffman, R. (2001). The ecology of cooperation: Theory and Decision Vol 50(2) Mar 2001, 101-118.
• Hogan, J. L., Fisher, R. H., & Morrison, B. J. (1973). Accuracy of perception and cooperative game behavior: Perceptual and Motor Skills Vol 37(2) Oct 1973, 391-398.
• Hokanson, J. E., Sacco, W. P., Blumberg, S. R., & Landrum, G. C. (1980). Interpersonal behavior of depressive individuals in a mixed-motive game: Journal of Abnormal Psychology Vol 89(3) Jun 1980, 320-332.
• Holt, D. J. (1999). An Empirical Model of Strategic Choice with an Application to Coordination Games: Games and Economic Behavior Vol 27(1) Apr 1999, 86-105.
• Holzinger, K. (2005). Tax Competition and Tax Co-Operation in the EU: The Case of Savings Taxation: Rationality and Society Vol 17(4) Nov 2005, 475-510.
• Hopthrow, T., Abrams, D., Frings, D., & Hulbert, L. G. (2007). Groupdrink: The effects of alcohol on intergroup competitiveness: Psychology of Addictive Behaviors Vol 21(2) Jun 2007, 272-276.
• Hottes, J. H., & Kahn, A. (1974). Sex differences in a mixed-motive conflict situation: Journal of Personality Vol 42(2) Jun 1974, 260-275.
• Howard, J. V. (1988). Cooperation in the Prisoner's Dilemma: Theory and Decision Vol 24(3) May 1988, 203-213.
• Howard, N. (1976). Prisoner's Dilemma: The solution by general metagames: Behavioral Science Vol 21(6) Nov 1976, 524-531.
• Hulbert, L. G., Correa da Silva, M. L., & Adegboyega, G. (2001). Cooperation in social dilemmas and allocentrism: A social values approach: European Journal of Social Psychology Vol 31(6) Nov-Dec 2001, 641-657.
• Hussy, W. (1979). Analysis of the need for information during a modified Prisoner's Dilemma game: Zeitschrift fur Experimentelle und Angewandte Psychologie Vol 26(4) 1979, 561-572.
• Hussy, W. (1979). Game behavior depending on kind of information and degree of risk in an alternating-sequential 2x2 game: Archiv fur Psychologie Vol 131(3) 1979, 233-248.
• Ingram, B. L., & Berger, S. E. (1977). Sex-role orientation, defensiveness, and competitiveness in women: Journal of Conflict Resolution Vol 21(3) Sep 1977, 501-518.
• Insko, C. A., Hoyle, R. H., Pinkley, R. L., Hong, G.-y., & et al. (1988). Individual-group discontinuity: The role of a consensus rule: Journal of Experimental Social Psychology Vol 24(6) Nov 1988, 505-519.
• Insko, C. A., Pinkley, R. L., Hoyle, R. H., Dalton, B., & et al. (1987). Individual versus group discontinuity: The role of intergroup contact: Journal of Experimental Social Psychology Vol 23(3) May 1987, 250-267.
• Insko, C. A., Schopler, J., Graetz, K. A., Drigotas, S. M., & et al. (1994). Interindividual-intergroup discontinuity in the prisoner's dilemma game: Journal of Conflict Resolution Vol 38(1) Mar 1994, 87-116.
• James, H. S., Jr. (2002). The trust paradox: A survey of economic inquiries into the nature of trust and trustworthiness: Journal of Economic Behavior & Organization Vol 47(3) Mar 2002, 291-307.
• Janssen, M. A. (2008). Evolution of cooperation in a one-shot Prisoner's Dilemma based on recognition of trustworthy and untrustworthy agents: Journal of Economic Behavior & Organization Vol 65(3-4) Mar 2008, 458-471.
• Jin, N., Hayashi, N., & Shinotsuka, H. (1993). An experimental study of Prisoner's Dilemma Network: Formation of committed relations among PD partners: Japanese Journal of Experimental Social Psychology Vol 33(1) Jul 1993, 21-30.
• Jin, N., Hayashi, N., & Shinotsuka, H. (1996). An experimental study of prisoner's dilemma network: Formation of committed relations among PD partners: Japanese Journal of Experimental Social Psychology Vol 35(3) Mar 1996, 292-303.
• Johnson, P. E. (1999). Simulation modeling in political science: American Behavioral Scientist Vol 42(10) Aug 1999, 1509-1530.
• Johnston, M., Markey, C., & Messe, L. A. (1973). A sex difference in labeling effects on behavior in the Prisoners' Dilemma game: Proceedings of the Annual Convention of the American Psychological Association 1973, 323-324.
• Jones, M., & Zhang, J. (2004). Rationality and bounded information in repeated games, with application to the iterated Prisoner's Dilemma: Journal of Mathematical Psychology Vol 48(5) Oct 2004, 334-354.
• Jozefowiez, J., Darcheville, J.-C., & Preux, P. (2000). An operant approach to the iterated Prisoners' Dilemma: Emergence of stable cooperation after indirect reinforcement of controlling behaviors in artificial learning agents: Revista Mexicana de Analisis de la Conducta Vol 26(2) Sep 2000, 211-227.
• Kahan, J. P. (1974). Rationality, the prisoner's dilemma, and population: Journal of Social Issues Vol 30(4) 1974, 189-210.
• Kane, T. R., Monteverde, F. J., & Tedeschi, J. T. (1976). Trust and the use of promises: Perceptual and Motor Skills Vol 42(2) Apr 1976, 439-443.
• Kassinove, H., Roth, D., Owens, S. G., & Fuller, J. R. (2002). Effects of trait anger and anger expression style on competitive attack responses in a wartime prisoner's dilemma game: Aggressive Behavior Vol 28(2) 2002, 117-125.
• Kay, A. C., & Ross, L. (2003). The perceptual push: The interplay of implicit cues and explicit situational construals on behavioral intentions in the Prisoner's Dilemma: Journal of Experimental Social Psychology Vol 39(6) Nov 2003, 634-643.
• Kefi, S., Bonnet, O., & Danchin, E. (2007). Accumulated gain in a prisoner's dilemma: Which game is carried out by the players? : Animal Behaviour Vol 74(4) Oct 2007, e1-e6.
• Keren, G., & Raub, W. (1993). Resolving social conflicts through hostage posting: Theoretical and empirical considerations: Journal of Experimental Psychology: General Vol 122(4) Dec 1993, 429-448.
• Kern, L. (1989). Cooperation and recognition: A comment on "Cooperation in the Prisoner's Dilemma" by J. V. Howard: Theory and Decision Vol 26(1) Jan 1989, 95-98.
• Key, C., & Aiello, L. C. (2000). A prisoner's dilemma model of the evolution of paternal care: Folia Primatologica Vol 71(1-2) Jan-Apr 2000, 77-92.
• Kim, S. H., & Webster, J. M. (2001). Getting competitors to cooperate: A comparison of three reciprocal strategies: Representative Research in Social Psychology Vol 25 2001, 9-19.
• Kirchkamp, O., & Nagel, R. (2007). Naive learning and cooperation in network experiments: Games and Economic Behavior Vol 58(2) Feb 2007, 269-292.
• Kiyonari, T., Tanida, S., & Yamagishi, T. (2000). Social exchange and reciprocity: Confusion or a heuristic? : Evolution and Human Behavior Vol 21(6) Nov 2000, 411-427.
• Knez, M., & Camerer, C. (2000). Increasing cooperation in prisoner's dilemmas by establishing a precedent of efficiency in coordination games: Organizational Behavior and Human Decision Processes Vol 82(2) Jul 2000, 194-216.
• Knight, G. P., & Mack, D. (1973). Race and behavior in the Prisoner's Dilemma game: Psychological Record Vol 23(1) Win 1973, 61-64.
• Kollock, P. (1996). The logic and practice of generosity: Reply: American Sociological Review Vol 61(2) Apr 1996, 341-346.
• Komorita, S. S. (1976). A model of the N-person Dilemma-Type Game: Journal of Experimental Social Psychology Vol 12(4) Jul 1976, 357-373.
• Komorita, S. S. (1987). Cooperative choice in decomposed social dilemmas: Personality and Social Psychology Bulletin Vol 13(1) Mar 1987, 53-63.
• Komorita, S. S., & Carnevale, P. (1992). Motivational arousal vs. decision framing in social dilemmas. Elmsford, NY: Pergamon Press.
• Komorita, S. S., Hilty, J. A., & Parks, C. D. (1991). Reciprocity and cooperation in social dilemmas: Journal of Conflict Resolution Vol 35(3) Sep 1991, 494-518.
• Kondo, T. (1990). Some notes on rational behavior, normative behavior, moral behavior, and cooperation: Journal of Conflict Resolution Vol 34(3) Sep 1990, 495-530.
• Kovacova, E., & Sarmany-Schuller, I. (2008). Influence of the level of selected self system components on decision making in the experimental PDG situation: Studia Psychologica Vol 50(1) 2008, 11-30.
• Kraines, D., & Kraines, V. (1989). Pavlov and the Prisoner's Dilemma: Theory and Decision Vol 26(1) Jan 1989, 47-79.
• Kraines, D., & Kraines, V. (1993). Learning to cooperate with Pavlov: An adaptive strategy for the iterated Prisoner's Dilemma with noise: Theory and Decision Vol 35(2) Sep 1993, 107-150.
• Kraines, D., & Kraines, V. (1995). Evolution of learning among Pavlov strategies in a competitive environment with noise: Journal of Conflict Resolution Vol 39(3) Sep 1995, 439-466.
• Kremer, J., Gallagher, A., Somerville, P., & Traylen, G. (1988). Social categorization and behaviour in mixed-motive games: A Northern Ireland study: Social Behaviour Vol 3(3) Sep 1988, 229-236.
• Kuhlman, D. M., & Marshello, A. F. (1975). Individual differences in game motivation as moderators of preprogrammed strategy effects in prisoner's dilemma: Journal of Personality and Social Psychology Vol 32(5) Nov 1975, 922-931.
• Larsen, J. D. (1987). Prisoner's dilemma as a model for understanding decisions: Teaching of Psychology Vol 14(4) Dec 1987, 230-231.
• Larsen, K. S. (1972). Attributed power, response strategies and non-zero sum game behavior: Psychological Reports Vol 30(3) Jun 1972, 821-822.
• Li, S., & Taplin, J. E. (2002). Examining whether there is a disjunction effect in Prisoner's Dilemma games: Chinese Journal of Psychology Vol 44(1) Jun 2002, 25-46.
• Liberman, V., Samuels, S. M., & Ross, L. (2004). The Name of the Game: Predictive Power of Reputations Versus Situational Labels in Determining Prisoner's Dilemma Game Moves: Personality and Social Psychology Bulletin Vol 30(9) Sep 2004, 1175-1185.
• Liebrand, W. B. (1983). A classification of social dilemma games: Simulation & Games Vol 14(2) Jun 1983, 123-138.
• Liebrand, W. B., Wilke, H. A., Vogel, R., & Wolters, F. J. (1986). Value orientation and conformity: A study using three types of social dilemma games: Journal of Conflict Resolution Vol 30(1) Mar 1986, 77-97.
• Lindskold, S., & Aronoff, J. R. (1980). Conciliatory strategies and relative power: Journal of Experimental Social Psychology Vol 16(2) Mar 1980, 187-198.
• Lindskold, S., Bennett, R., & Wayner, M. (1976). Retaliation level as a foundation for subsequent conciliation: Behavioral Science Vol 21(1) Jan 1976, 13-18.
• Lindskold, S., Betz, B., & Walters, P. S. (1986). Transforming competitive or cooperative climates: Journal of Conflict Resolution Vol 30(1) Mar 1986, 99-114.
• Lindskold, S., & Finch, M. L. (1981). Styles of announcing conciliation: Journal of Conflict Resolution Vol 25(1) Mar 1981, 145-155.
• Lindskold, S., & Han, G. (1988). GRIT as a foundation for intergrative bargaining: Personality and Social Psychology Bulletin Vol 14(2) Jun 1988, 335-345.
• Lindskold, S., & Han, G. (1988). Group resistance to influence by a conciliatory member: Small Group Behavior Vol 19(1) Feb 1988, 19-34.
• Lindskold, S., Han, G., & Betz, B. (1986). The essential elements of communication in the GRIT strategy: Personality and Social Psychology Bulletin Vol 12(2) Jun 1986, 179-186.
• Lindskold, S., Han, G., & Betz, B. (1986). Repeated persuasion in interpersonal conflict: Journal of Personality and Social Psychology Vol 51(6) Dec 1986, 1183-1188.
• Lindskold, S., Walters, P. S., & Koutsourais, H. (1983). Cooperators, competitors, and response to GRIT: Journal of Conflict Resolution Vol 27(3) Sep 1983, 521-532.
• lmhof, L. A., Fudenberg, D., & Nowak, M. A. (2005). Evolutionary cycles of cooperation and defection: PNAS Proceedings of the National Academy of Sciences of the United States of America Vol 102(31) Aug 2005, 10797-10800.
• Lodewijkx, H. F. M. (2001). Individual-group continuity in cooperation and competition under varying communication conditions: Current Research in Social Psychology Vol 6(12) May 2001, No Pagination Specified.
• Lodewijkx, H. F. M., Rabbie, J. M., & Visser, L. (2006). "Better to be safe than to be sorry": Extinguishing the individual-group discontinuity effect in competition by cautious reciprocation: European Review of Social Psychology Vol 17 2006, 185-232.
• Lohmann, S. (1997). Linkage politics: Journal of Conflict Resolution Vol 41(1) Feb 1997, 38-67.
• Lomborg, B. (1996). Nucleus and shield: The evolution of social structure in the iterated prisoner's dilemma: American Sociological Review Vol 61(2) Apr 1996, 278-307.
• Lomi, A., & Larsen, E. (1997). Cellular automata in the prisoner's dilemma game: A computational perspective on the mechanics of strategic interactions: Sistemi Intelligenti Vol 9(1) Apr 1997, 67-91.
• Lopez, L. C. (1995). Correlations of selected cognitive styles with cooperation in a prisoner's dilemma game: Psychological Reports Vol 77(1) Aug 1995, 242.
• Luksik, I. (1990). Variability and success in an experimental game: A probe into creating causal scenarios: Ceskoslovenska Psychologie Vol 34(4) 1990, 289-293.
• Lumsden, M. (1973). The Cyprus conflict as a Prisoner's Dilemma game: Journal of Conflict Resolution Vol 17(1) Mar 1973, 7-32.
• Macia, A., Perez-Llantada, C., & Gonzalez, J. L. (1996). Game theory and type A behavior: An experimental study: Revista de Psicologia General y Aplicada Vol 49(1) Jan 1996, 127-134.
• Mack, D. (1972). "Leader": An unbiased mixed-motive game? : Psychologische Beitrage Vol 14(2) 1972, 244-252.
• Mack, D. (1976). Status and behavior in the reiterated Prisoner's Dilemma game: Psychological Record Vol 26(4) Fal 1976, 529-532.
• Mack, D., & Knight, G. P. (1974). Identification of other players' characteristics in the reiterated Prisoner's Dilemma: Psychological Record Vol 24(1) Win 1974, 93-100.
• Mack, D., Williams, J. G., & Kremer, J. M. (1979). Perception of a simulated other player and behavior in the reiterated Prisoner's Dilemma game: Psychological Record Vol 29(1) Win 1979, 43-48.
• Mailath, G. J., Obara, I., & Sekiguchi, T. (2002). The Maximum Efficient Equilibrium Payoff in the Repeated Prisoners' Dilemma: Games and Economic Behavior Vol 40(1) Jul 2002, 99-122.
• Majeski, S. J., & Fricks, S. (1995). Conflict and cooperation in international relations: Journal of Conflict Resolution Vol 39(4) Dec 1995, 622-645.
• Majolo, B., Ames, K., Brumpton, R., Garratt, R., Hall, K., & Wilson, N. (2006). Human friendship favours cooperation in the Iterated Prisoner's Dilemma: Behaviour Vol 143(11) Nov 2006, 1383-1395.
• Mansbridge, J. (1995). Rational choice gains by losing: Political Psychology Vol 16(1) Mar 1995, 137-155.
• Manz, W. (1972). A simple apparatus for two person matrix games: Zeitschrift fur Experimentelle und Angewandte Psychologie Vol 19(1) 1972, 130-140.
• Marinoff, L. (1992). Maximizing expected utilities in the prisoner's dilemma: Journal of Conflict Resolution Vol 36(1) Mar 1992, 183-216.
• Matsuda, M., & Yamagishi, T. (2001). Trust and cooperation: An experimental study of PD with choice of dependence: Japanese Journal of Psychology Vol 72(5) Dec 2001, 413-421.
• Matsumoto, D., Haan, N., Yabrove, G., Theodorou, P., & Carney, C. C. (1986). Preschoolers' moral actions and emotions in Prisoner's Dilemma: Developmental Psychology Vol 22(5) Sep 1986, 663-670
• McGillivray, F., & Smith, A. (2005). The Impact of Leadership Turnover and Domestic Institutions on International Cooperation: Journal of Conflict Resolution Vol 49(5) Oct 2005, 639-660.
• McGinnis, M. D. (1986). Issue linkage and the evolution of international cooperation: Journal of Conflict Resolution Vol 30(1) Mar 1986, 141-170.
• McNamara, J. M., Barta, Z., & Houston, A. I. (2004). Variation in behaviour promotes cooperation in the Prisoner's Dilemma game: Nature Vol 428(6984) Apr 2004, 745-748.
• McNeel, S. P. (1973). Training cooperation in the Prisoner's Dilemma: Journal of Experimental Social Psychology Vol 9(4) Jul 1973, 335-348.
• Messe, L. A., Dawson, J. E., & Lane, I. M. (1973). Equity as a mediator of the effect of reward level on behavior in the Prisoner's Dilemma game: Journal of Personality and Social Psychology Vol 26(1) Apr 1973, 60-65.
• Messick, D. M., & Liebrand, W. B. (1993). Computer simulations of the relation between individual heuristics and global cooperation in Prisoner's Dilemmas: Social Science Computer Review Vol 11(3) Fal 1993, 301-312.
• Messick, D. M., & Liebrand, W. B. G. (1995). Individual heuristics and the dynamics of cooperation in large groups: Psychological Review Vol 102(1) Jan 1995, 131-145.
• Messick, D. M., & Liebrand, W. B. G. (1997). Levels of analysis and the explanation of the costs and benefits of cooperation: Personality and Social Psychology Review Vol 1(2) 1997, 129-139.
• Mesterton-Gibbons, M., & Adams, E. S. (2002). The economics of animal cooperation: Science Vol 298(5601) Dec 2002, 2146-2147.
• Milinski, M. (1987). TIT FOR TAT in sticklebacks and the evolution of cooperation: Nature Vol 325(6103) Jan-Feb 1987, 433-435.
• Miller, D. T., Downs, J. S., & Prentice, D. A. (1998). Minimal conditions for the creation of a unit relationship: The social bond between birthdaymates: European Journal of Social Psychology Vol 28(3) May-Jun 1998, 475-481.
• Miller, D. T., & Holmes, J. G. (1975). The role of situational restrictiveness on self-fulfilling prophecies: A theoretical and empirical extension of Kelley and Stahelski's triangle hypothesis: Journal of Personality and Social Psychology Vol 31(4) Apr 1975, 661-673.
• Minkler, L. P., & Miceli, T. J. (2004). Lying, Integrity, and Cooperation: Review of Social Economy Vol 62(1) Mar 2004, 27-50.
• Mirabile, C. S., & Glueck, B. C. (1979). Motion sickness susceptibility and solution choice in a pragmatic paradox: Neuropsychobiology Vol 5(1) 1979, 46-49.
• Misra, S., & Kalro, A. (1979). Triangle effect and the connotative meaning of trust in Prisoner's Dilemma: A cross cultural study: International Journal of Psychology Vol 14(4) 1979, 255-263.
• Molander, P. (1985). The optimal level of generosity in a selfish, uncertain environment: Journal of Conflict Resolution Vol 29(4) Dec 1985, 611-618.
• Molander, P. (1992). The prevalence of free riding: Journal of Conflict Resolution Vol 36(4) Dec 1992, 756-771.
• Monderer, D., & Tennenholtz, M. (1999). Distributed Games: Games and Economic Behavior Vol 28(1) Jul 1999, 55-72.
• Monterosso, J., Ainslie, G., Mullen, P. A. C. P. T., & Gault, B. (2002). The fragility of cooperation: A false feedback study of a sequential iterated prisoner's dilemma: Journal of Economic Psychology Vol 23(4) Aug 2002, 437-448.
• Monteverde, F. J., Paschke, R., & Tedeschi, J. T. (1974). The effectiveness of honesty and deceit as influence tactics: Sociometry Vol 37(4) Dec 1974, 583-591.
• Moore, M. F., & Mack, D. (1972). Dominance-ascendance and behavior in the reiterated Prisoner's Dilemma game: Acta Psychologica Vol 36(6) Dec 1972, 480-491.
• Mori, K. (1996). Effects of trust and communication on cooperative choice in a two-person prisoner's dilemma game: Japanese Journal of Experimental Social Psychology Vol 35(3) Mar 1996, 324-336.
• Mori, K. (1998). Information preferences and social value orientations in a prisoner's dilemma game: Japanese Journal of Experimental Social Psychology Vol 38(1) Jun 1998, 48-62.
• Morris, M. W., Sim, D. L. H., & Girotto, V. (1995). Time of decision, ethical obligation, and causal illusion: Temporal cues and social heuristics in the prisoner's dilemma. Thousand Oaks, CA: Sage Publications, Inc.
• Morris, M. W., Sim, D. L. H., & Girotto, V. (1998). Distinguishing sources of cooperation in the one-round prisoner's dilemma: Evidence for cooperative decisions based on the illusion of control: Journal of Experimental Social Psychology Vol 34(5) Sep 1998, 494-512.
• Mossel, E., & Roch, S. (2007). Slow emergence of cooperation for win-stay lose-shift on trees: Machine Learning Vol 67(1-2) May 2007, 7-22.
• Mukherji, A., Rajan, V., & Slagle, J. R. (1996). Robustness of cooperation: Nature Vol 379(6561) Jan 1996, 125-126.
• Murata, K. (1982). Attribution processes in a mixed-motive interaction: The role of active observer's behavior: Behaviormetrika No 12 Jul 1982, 47-61.
• Murnighan, J. K. (1991). Cooperating when you know your outcomes will differ: Simulation & Gaming Vol 22(4) Dec 1991, 463-475.
• Murnighan, J. K., & King, T. R. (1992). The effects of leverage and payoffs on cooperative behavior in asymmetric dilemmas. Elmsford, NY: Pergamon Press.
• Murnighan, J. K., & Roth, A. E. (1983). Expecting continued play in prisoner's dilemma games: A test of several models: Journal of Conflict Resolution Vol 27(2) Jun 1983, 279-300.
• Mushkat, M. (1985). Understanding the Prisoner's dilemma and its public policy implications: Asian Journal of Psychology & Education Vol 15(3) Jul 1985, 1-8.
• Myers, D. G., & Bach, P. J. (1976). Group discussion effects on conflict behavior and self-justification: Psychological Reports Vol 38(1) Feb 1976, 135-140.
• Nauta, D., & Hoeksta, J. (1995). Effective choice in the single-shot Prisoner's Dilemma tournament: Theory and Decision Vol 39(1) Jul 1995, 1-30.
• Nelson, S. D. (1973). Objective power, subjective power, and causal attribution in social interaction: Proceedings of the Annual Convention of the American Psychological Association 1973, 325-326.
• Neuberg, S. L. (1988). Behavioral implications of information presented outside of conscious awareness: The effect of subliminal presentation of trait information on behavior in the Prisoner's Dilemma Game: Social Cognition Vol 6(3) 1988, 207-230.
• Nishizaki, I., Sakawa, M., & Katagiri, H. (2004). Influence of environmental changes on cooperative behavior in the Prisoner's Dilemma game on an artificial social model: Applied Artificial Intelligence Vol 18(7) Aug 2004, 651-671.
• Noe, R. (1990). A Veto game played by baboons: A challenge to the use of the Prisoner's Dilemma as a paradigm for reciprocity and cooperation: Animal Behaviour Vol 39(1) Jan 1990, 78-90.
• Nowak, M., & Sigmund, K. (1993). A strategy of win-stay, lose-shift that outperforms tit-for-tat in the Prisoner's Dilemma game: Nature Vol 364(6432) Jul 1993, 56-58.
• Nowak, M. A. (1996). "Robustness of cooperation": Nowak et al reply: Nature Vol 379(6561) Jan 1996, 126.
• Nowak, M. A., & May, R. M. (1992). Evolutionary games and spatial chaos: Nature Vol 359(6398) Oct 1992, 826-829.
• Nowak, M. A., Sasaki, A., Taylor, C., & Fudenberg, D. (2004). Emergence of cooperation and evolutionary stability in finite populations: Nature Vol 428(6983) Apr 2004, 646-650.
• Nowak, M. A., & Sigmund, K. (1995). Invasion dynamics of the finitely repeated prisoner's dilemma: Games and Economic Behavior Vol 11(2) Nov 1995, 364-390.
• Nydegger, R. V. (1974). Information processing complexity and gaming behavior: The Prisoner's Dilemma: Behavioral Science Vol 19(3) May 1974, 204-210.
• Nydegger, R. V. (1980). The effects of information processing complexity and interpersonal cue availability on strategic play in a mixed-motive game: Journal of Personality Vol 48(1) Mar 1980, 38-53.
• Oda, R. (1997). Biased face recognition in the prisoner's dilemma game: Evolution and Human Behavior Vol 18(5) Sep 1997, 309-315.
• Oliver, P. (1984). Rewards and punishments as selective incentives: An apex game: Journal of Conflict Resolution Vol 28(1) Mar 1984, 123-148.
• Orbell, J., Dawes, R., & Schwartz-Shea, P. (1994). Trust, social categories, and individuals: The case of gender: Motivation and Emotion Vol 18(2) Jun 1994, 109-128.
• Orbell, J. M., & Dawes, R. M. (1993). Social welfare, cooperators' advantage, and the option of not playing the game: American Sociological Review Vol 58(6) Dec 1993, 787-800.
• Orcutt, J. D., & Anderson, R. E. (1977). Social interaction, dehumanization and the "computerized other." Sociology & Social Research Vol 61(3) Apr 1977, 380-397.
• Orkin, M. (1987). Balanced strategies for Prisoner's Dilemma: Journal of Conflict Resolution Vol 31(1) Mar 1987, 186-191.
• Oskamp, S. (1974). Comparison of sequential and simultaneous responding, matrix, and strategy variables in a Prisoner's Dilemma game: Journal of Conflict Resolution Vol 18(1) Mar 1974, 107-116.
• Oskamp, S., & Kleinke, C. (1971). "Amount of Reward as a Variable in the Prisoner's Dilemma Game": Erratum: Journal of Personality and Social Psychology Vol 17(1) Jan 1971, 112.
• Outkin, A. V. (2003). Cooperation and local interactions in the Prisoners' Dilemma Game: Journal of Economic Behavior & Organization Vol 52(4) Dec 2003, 481-503.
• Ozono, H., Yoshikawa, S., & Watabe, M. (2006). The effects of information concerning cooperativeness on face memory and behavioral choices: Using the social exchange task: The Japanese Journal of Cognitive Psychology Vol 3(2) Mar 2006, 157-166.
• Packer, M. J. (1985). The structure of moral action: A hermeneutic study of moral conflict: Contributions to Human Development Vol 13 1985, 158.
• Paese, P. W., & Stang, S. J. (1998). Adaptation-level phenomena and the prevalence of cooperation: Social Psychology Quarterly Vol 61(2) Jun 1998, 172-183.
• Pahre, R. (1994). Multilateral cooperation in an iterated prisoner's dilemma: Journal of Conflict Resolution Vol 38(2) Jun 1994, 326-352.
• Palombo, S. R. (1997). The prisoner's dilemma: Game theory and the therapeutic alliance: Psychoanalytic Quarterly Vol 66(4) Oct 1997, 628-641.
• Parks, C. D., Henager, R. F., & Scamahorn, S. D. (1996). Trust and reactions to messages of intent in social dilemmas: Journal of Conflict Resolution Vol 40(1) Mar 1996, 134-151.
• Parks, C. D., Rumble, A. C., & Posey, D. C. (2002). The effects of envy on reciprocation in a social dilemma: Personality and Social Psychology Bulletin Vol 28(4) Apr 2002, 509-520.
• Patterson, A. H., & Boles, W. E. (1974). The effects of personal space variables upon approach and attitudes toward the other in a Prisoner's Dilemma game: Personality and Social Psychology Bulletin Vol 1(1) 1974, 364-366.
• Piburn, M. D. (1977). Teaching about science and society: Moral judgment and the Prisoner's Dilemma: Theory and Research in Social Education Vol 5(2) Aug 1977, 20-30.
• Pilisuk, M., Brandes, B., & Van den Hove, D. (1976). Deceptive sounds: Ilicit communication in the laboratory: Behavioral Science Vol 21(6) Nov 1976, 515-523.
• Pincus, J., & Bixenstine, V. E. (1977). Cooperation in the decomposed Prisoner's Dilemma game: A question of revealing or concealing information: Journal of Conflict Resolution Vol 21(3) Sep 1977, 519-530.
• Pincus, J., & Bixenstine, V. E. (1979). Cognitive factors and cooperation in the Prisoner's Dilemma game: Psychological Record Vol 29(4) Fal 1979, 463-471.
• Plous, S. (1987). Perceptual illusions and military realities: Results from a computer-simulated arms race: Journal of Conflict Resolution Vol 31(1) Mar 1987, 5-33.
• Plous, S. (1993). Prisoner's Dilemma or Perceptual Dilemma? Journal of Peace Research, Vol. 30, No. 2, 163-179.
• Polozova, T. A. (1980). Methodological problems in the study of interpersonal conflicts within groups: Voprosy Psychologii No 4 Jul-Aug 1980, 123-129.
• Pulkowski-Rebellius, H. B. (1973). Conflict and sociometric status: Game theory investigation of 6th-8th grade pupils from 30 elementary schools: Archiv fur Psychologie Vol 125(2-3) 1973, 113-138.
• Rachlin, H., Brown, J., & Baker, F. (2001). Reinforcement and punishment in the Prisoner's Dilemma Game. San Diego, CA: Academic Press.
• Rada, F. M., Taracena, M. T. d. L., & Rodriguez, M. A. M. (2003). Antisocial personality disorder evaluation with the prisoner's dilemma: Actas Espanolas de Psiquiatria Vol 31(6) Nov-Dec 2003, 307-314.
• Rapoport, A. (1975). Comment on Brams's discussion of Newcomb's paradox: Journal of Conflict Resolution Vol 19(4) Dec 1975, 613-619.
• Rapoport, A. (1975). Some comments on "Prisoner's Dilemma: Metagames and other solutions." Behavioral Science Vol 20(3) May 1975, 206-208.
• Rapoport, A. (1985). Editorial comment on articles by Diekmann and Molander: Journal of Conflict Resolution Vol 29(4) Dec 1985, 619-622.
• Rapoport, A. (1988). Experiments with n-person social traps: I. Prisoner's Dilemma, Weak Prisoner's Dilemma, Volunteer's Dilemma, and Largest Number: Journal of Conflict Resolution Vol 32(3) Sep 1988, 457-472.
• Reeves, E. B., & Pitts, T. C. (1996). Cooperative strategies in low-noise environments: Comment: American Sociological Review Vol 61(2) Apr 1996, 338-341.
• Reka, J., & Boglarka, S. (2005). Domain-specific Decisions in Non-zero Amount Games in Function of the Specialization: Erdelyi Pszichologiai Szemle Vol 6(4) Dec 2005, 361-384.
• Richards, D. (2001). Reciprocity and shared knowledge structures in the prisoner's dilemma game: Journal of Conflict Resolution Vol 45(5) Oct 2001, 621-635.
• Rilling, J. K., Glenn, A. L., Jairam, M. R., Pagnoni, G., Goldsmith, D. R., Elfenbein, H. A., et al. (2007). Neural correlates of social cooperation and non-cooperation as a function of psychopathy: Biological Psychiatry Vol 61(11) Jun 2007, 1260-1271.
• Roberts, G. (1997). Testing mutualism: A commentary on Clements & Stephens: Animal Behaviour Vol 53(6) Jun 1997, 1361-1362.
• Robinson, M. (1975). Critique and comment: Behavioral Science Vol 20(3) May 1975, 201-205.
• Rosenthal, R. W. (1980). New equilibria for noncooperative two-person games: Journal of Mathematical Sociology Vol 7(1) 1980, 15-26.
• Roth, A. E., & Murnighan, J. K. (1978). Equilibrium behavior and repeated play of the Prisoner's Dilemma: Journal of Mathematical Psychology Vol 17(2) Apr 1978, 189-198.
• Saito, I. (1975). A comparative study of game behavior and choice motive in the sequential choice vs. the simultaneous choice in Prisoner's Dilemma game: Japanese Journal of Experimental Social Psychology Vol 15(2) Dec 1975, 129-141.
• Saito, K. (1991). The effects of interpersonal orientation in prisoner's dilemma game with a seeking choice: Japanese Journal of Experimental Social Psychology Vol 31(2) Nov 1991, 121-131.
• Sanabria, F., Baker, F., & Rachlin, H. (2003). Learning by pigeons playing against tit-for-tat in an operant prisoner's dilemma: Learning & Behavior Vol 31(4) Nov 2003, 318-331.
• Sandole, D. J. D. (2003). Validating simulation-based models of conflict: Simulation & Gaming Vol 34(2) Jun 2003, 249-280.
• Santa-Barbara, J., & Epstein, N. B. (1973). Conflict behavior in clinical families: Interaction patterns and stable outcomes: Proceedings of the Annual Convention of the American Psychological Association 1973, 319-320.
• Schneider, H. D. (1973). The effects of the partner's strategy and amount of risk on playing behavior and reward in a modification of the Prisoner's Dilemma game: Zeitschrift fur Sozialpsychologie Vol 4(3) 1973, 220-230.
• Schopler, J., Insko, C. A., Graetz, K. A., Drigotas, S. M., & et al. (1991). The generality of the individual-group discontinuity effect: Variations in positivity-negativity of outcomes, players' relative power, and magnitude of outcomes: Personality and Social Psychology Bulletin Vol 17(6) Dec 1991, 612-624.
• Schuessler, R. (1989). Exit threats and cooperation under anonymity: Journal of Conflict Resolution Vol 33(4) Dec 1989, 728-749.
• Schuessler, R. (1989). The gradual decline of cooperation: Endgame effects in evolutionary game theory: Theory and Decision Vol 26(2) Mar 1989, 133-155.
• Schuessler, R. (1990). Threshold effects and the decline of cooperation: Journal of Conflict Resolution Vol 34(3) Sep 1990, 476-494.
• Schulz, U., & Hesse, W. (1978). A model for gaming behavior in sequences of Prisoner's Dilemma games in consideration of expectations: Psychologische Beitrage Vol 20(4) 1978, 551-570.
• Schulz, U., & May, T. (1983). A model of behavior in sequences of conflict games taking into consideration anticipations and subjective certainties: Zeitschrift fur Sozialpsychologie Vol 14(4) 1983, 322-340.
• Schuster, B. (1999). Nice guys or bad guys? Victims of mobbing/bullying and peer rejection in the prisoner's dilemma paradigm: Zeitschrift fur Sozialpsychologie Vol 30(2-3) Jul 1999, 179-193.
• Schweitzer, M. E., DeChurch, L. A., & Gibson, D. E. (2005). Conflict frames and the use of deception: Are competitive negotiators less ethical? : Journal of Applied Social Psychology Vol 35(10) Oct 2005, 2123-2149.
• Seale, D. A., Arend, R. J., & Phelan, S. (2006). Modeling alliance activity: Opportunity cost effects and manipulations in an iterated prisoner's dilemma with exit option: Organizational Behavior and Human Decision Processes Vol 100(1) May 2006, 60-75.
• Serrano, R., & Zapater, I. (1998). The Three-Legged Race: Cooperating to Compete: Games and Economic Behavior Vol 22(2) Feb 1998, 343-363.
• Shaw, J. I. (1976). Response-contingent payoffs and cooperative behavior in the Prisoner's Dilemma game: Journal of Personality and Social Psychology Vol 34(5) Nov 1976, 1024-1033.
• Sheldon, K. M. (1999). Learning the lessons of tit-for-tat: Even competitors can get the message: Journal of Personality and Social Psychology Vol 77(6) Dec 1999, 1245-1253.
• Sheldon, K. M., Sheldon, M. S., & Osbaldiston, R. (2000). Prosocial values and group assortation within an N-person Prisoner's Dilemma Game: Human Nature Vol 11(4) 2000, 387-404.
• Sheng, C. L. (1994). A note on the prisoner's dilemma: Theory and Decision Vol 36(3) May 1994, 233-246.
• Sheposh, J. P., & Gallo, P. S. (1973). Asymmetry of payoff structure and cooperative behavior in the Prisoner's Dilemma game: Journal of Conflict Resolution Vol 17(2) Jun 1973, 321-333.
• Shimizu, T. (1997). Evolution of cooperation in the finitely repeated prisoner's dilemma: Japanese Journal of Behaviormetrics Vol 24(1) Jun 1997, 101-111.
• Shinada, M. (2005). Linking behavior in a social dilemma to outcome in another exchange: An experimental study of social dilemma resolution: Japanese Journal of Psychology Vol 76(2) Jun 2005, 163-168.
• Shinada, M., & Yamagishi, T. (2007). Punishing free riders: Direct and indirect promotion of cooperation: Evolution and Human Behavior Vol 28(5) Sep 2007, 330-339.
• Shinada, M., & Yamagishi, T. (2008). "Punishing free riders: Direct and indirect promotion of cooperation": Erratum: Evolution and Human Behavior Vol 29(2) Mar 2008, 147.
• Skelton, J. A. (1992). Teaching tip: Using the prisoner's dilemma as a class demonstration of situationism: Contemporary Social Psychology Vol 16(1-2) Jun 1992, 16-20.
• Skotko, V., Langmeyer, D., & Lundgren, D. (1974). Sex differences as artifact in the Prisoner's Dilemma game: Journal of Conflict Resolution Vol 18(4) Dec 1974, 707-713.
• Slusher, E. A., Roering, K. J., & Rose, G. L. (1974). The effects of commitment to future interaction in single plays of three games: Behavioral Science Vol 19(2) Mar 1974, 119-132.
• Smith, N. S., Vernon, C. R., & Tarte, R. D. (1975). Ramdom strategies and sex differences in the Prisoner's Dilemma game: Journal of Conflict Resolution Vol 19(4) Dec 1975, 643-658.
• Snow, P. (1985). The value of information in Newcomb's Problem and the Prisoners' Dilemma: Theory and Decision Vol 18(2) Mar 1985, 129-133.
• Sommer, R. (1982). The district attorney's dilemma: Experimental games and the real world of plea bargaining: American Psychologist Vol 37(5) May 1982, 526-532.
• Speer, D. C. (1972). Variations of the Prisoner's Dilemma game as measures of marital interaction: Sequential dyadic measures: Journal of Abnormal Psychology Vol 80(3) Dec 1972, 287-293.
• Srivastava, A. K. (1985). Cooperation and competition in Prisoner's Dilemma game: Psychological Studies Vol 30(2) Jul 1985, 116-120.
• Stark, O. (2004). Cooperation and wealth: Journal of Economic Behavior & Organization Vol 53(1) Jan 2004, 109-115.
• Steinfatt, T. M. (1973). The Prisoner's Dilemma and a creative alternative game: The effects of communications under conditions of real reward: Simulation & Games Vol 4(4) Dec 1973, 389-409.
• Stephens, D. W., & Anderson, J. P. (1997). Reply to Roberts: Cooperation is an outcome, not a mechanism: Animal Behaviour Vol 53(6) Jun 1997, 1363-1364.
• Stephens, D. W., McLinn, C. M., & Stevens, J. R. (2002). Discounting and reciprocity in an Iterated Prisoner's Dilemma: Science Vol 298(5601) Dec 2002, 2216-2218.
• Steuden, S. (1979). Psychological analysis of behaviour in emotionally balanced and imbalanced groups in conflict situations: Przeglad Psychologiczny Vol 22(3) 1979, 507-515.
• Stix, A. H. (1974). Chlordiazepoxide (Librium): The effects of a minor tranquilizer on strategic choice behavior in the Prisoner's Dilemma: Journal of Conflict Resolution Vol 18(3) Sep 1974, 373-394.
• Stockard, J., O'Brien, R. M., & Peters, E. (2007). The use of mixed models in a modified Iowa Gambling Task and a prisoner's dilemma game: Judgment and Decision Making Vol 2(1) Feb 2007, 9-22.
• Stone, B., Jones, C., & Betz, B. (1996). Response of cooperators and competitors in a simulated arms race: Psychological Reports Vol 79(3, Pt 2) Dec 1996, 1101-1102.
• Streich, P., & Levy, J. S. (2007). Time Horizons, Discounting, and Intertemporal Choice: Journal of Conflict Resolution Vol 51(2) Apr 2007, 199-226.
• Stuart, H. W., Jr. (1997). Common belief of rationality in the finitely repeated Prisoners' Dilemma: Games and Economic Behavior Vol 19(1) Apr 1997, 133-143.
• Stults, D. M., & Meese, L. A. (1985). Behavioral consistency: The impact of public versus private statements of intentions: Journal of Social Psychology Vol 125(2) Apr 1985, 277-278.
• Summers, D. A., Peirce, S., Olen, D., & Baranowski, T. (1972). Strategy detection in the Prisoner's Dilemma game: Journal of Social Psychology Vol 88(1) Oct 1972, 131-138.
• Swistak, P. (1989). How to resist invasion in the repeated Prisoner's Dilemma game: Behavioral Science Vol 34(2) Apr 1989, 151-153.
• Takigawa, T. (1989). Metagame, supergame, and hypergame: Japanese Psychological Review Vol 32(3) 1989, 333-348.
• Tanida, S., & Yamagishi, T. (2004). The effect of empathy on accuracy of behavior prediction in social exchange situation: Japanese Journal of Psychology Vol 74(6) Feb 2004, 512-520.
• Tedeschi, J. T. (1979). Frustration, fantasy aggression, and the exercise of coercive power: Perceptual and Motor Skills Vol 48(1) Feb 1979, 215-219.
• Tennenholtz, M. (2004). Program equilibrium: Games and Economic Behavior Vol 49(2) Nov 2004, 363-373.
• Terai, S., Morita, Y., & Yamagishi, T. (2003). Trust and assurance of cooperation in ongoing relations: An experimental study using the prisoner's dilemma with variable dependence: The Japanese Journal of Social Psychology Vol 18(3) Mar 2003, 172-179.
• Terhune, K. W. (1974). "Wash-in," "wash-out," and systemic effects in extended Prisoner's Dilemma: Journal of Conflict Resolution Vol 18(4) Dec 1974, 656-685.
• Thomas, E. A., & Feldman, M. W. (1988). Behavior-dependent contexts for repeated plays of the Prisoner's Dilemma: Journal of Conflict Resolution Vol 32(4) Dec 1988, 699-726.
• Tilley, J. J. (1996). Prisoner's dilemma from a moral point of view: Theory and Decision Vol 41(2) Sep 1996, 187-193.
• Tognoli, J. (1975). Reciprocation of generosity and knowledge of game termination in the decomposed Prisoner's Dilemma game: European Journal of Social Psychology Vol 5(3) 1975, 297-313.
• Tomer, J. F. (1987). Productivity through intra-firm cooperation: A behavioral economic analysis: Journal of Behavioral Economics Vol 16(1) Spr 1987, 83-95.
• Tomochi, M. (2004). Defectors' niches: Prisoner's dilemma game on disordered networks: Social Networks Vol 26(4) Oct 2004, 309-321.
• Turner, P. E., & Chao, L. (1999). Prisoner's dilemma in an RNA virus: Nature Vol 398(6726) Apr 1999, 441-443.
• Tversky, A. (1967). The Psychologist's Dilemma: PsycCRITIQUES Vol 12 (9), Sep, 1967.
• Tyson, G. A., Schlachter, A., & Cooper, S. (1988). Game playing strategy as an indicator of racial prejudice among South African students: Journal of Social Psychology Vol 128(4) Aug 1988, 473-485.
• van de Sande, J. P. (1973). An investigation of the behavioral differences between men and women with regard to game theory: Nederlands Tijdschrift voor de Psychologie en haar Grensgebieden Vol 28(5) Oct 1973, 327-341.
• Van den Bergh, B., & Dewitte, S. (2006). The robustness of the "raise-the-stakes" strategy: Coping with exploitation in noisy prisoner's dilemma games: Evolution and Human Behavior Vol 27(1) Jan 2006, 19-28.
• Van der Sanden, A. L. (1978). Latent Markov chain analysis of a value conflict in Prisoner's Dilemma games: British Journal of Mathematical and Statistical Psychology Vol 31(2) Nov 1978, 126-143.
• Van Lange, P. A., Liebrand, W. B., Kiers, H. A., & Zwaal, W. (1989). Reasons for and attributes of choice behavior in an N-person prisoner's dilemma: Nederlands Tijdschrift voor de Psychologie en haar Grensgebieden Vol 44(5) Jul 1989, 225-234.
• Van Lange, P. A., Liebrand, W. B., & Kuhlman, D. M. (1990). Causal attribution of choice behavior in three N-Person Prisoner's Dilemmas: Journal of Experimental Social Psychology Vol 26(1) Jan 1990, 34-48.
• Vega-Redondo, F. (1994). Bayesian boundedly rational agents play the Finitely Repeated Prisoner's Dilemma: Theory and Decision Vol 36(2) Mar 1994, 187-206.
• Vlaev, I., & Chater, N. (2006). Game relativity: How context influences strategic decision making: Journal of Experimental Psychology: Learning, Memory, and Cognition Vol 32(1) Jan 2006, 131-149.
• Vlaev, I., & Chater, N. (2007). Context effects in games: Local versus global sequential effects on choice in the prisoner's dilemma game: Judgment and Decision Making Vol 2(6) Dec 2007, 380-389.
• Vlaev, I., & Chater, N. (2008). Debiasing context effects in strategic decisions: Playing against a consistent opponent can correct perceptual but not reinforcement: Judgment and Decision Making Vol 3(6) Aug 2008, 463-474.
• Volij, O. (2002). In Defense of DEFECT: Games and Economic Behavior Vol 39(2) May 2002, 309-321.
• Watabe, M., Terai, S., Hayashi, N., & Yamagishi, T. (1996). Cooperation in the one-shot Prisoner's Dilemma based on expectations of reciprocity: Japanese Journal of Experimental Social Psychology Vol 36(2) Dec 1996, 183-196.
• Watanabe, Y., & Yamagishi, T. (1997). When "false consensus" stops being "false": An experimental study of a 1-shot prisoner's dilemma situation: Japanese Journal of Psychology Vol 67(6) Feb 1997, 421-428.
• Watanabe, Y., & Yamagishi, T. (1999). Emergence of strategies in a selective play environment with geographic mobility: A computer simulation. New York, NY: Psychology Press.
• Wein, S. (1985). Prisoners' dilemmas, tuism, and rationality: Simulation & Games Vol 16(1) Mar 1985, 23-31.
• Weinlader, H. G. (1981). Mixed social interaction between handicapped and non-handicapped people: Some theoretical considerations: International Journal of Rehabilitation Research Vol 4(4) Dec 1981, 511-517.
• Wildschut, T., Insko, C. A., & Pinter, B. (2007). Interindividual-intergroup discontinuity as a joint function of acting as a group and interacting with a group: European Journal of Social Psychology Vol 37(2) Mar-Apr 2007, 390-399.
• Wiley, M. G. (1973). Sex roles in games: Sociometry Vol 36(4) Dec 1973, 526-541.
• Winkler, I., Jonas, K., & Rudolph, U. (2008). On the usefulness of memory skills in social interactions: Modifying the iterated prisoner's dilemma: Journal of Conflict Resolution Vol 52(3) Jun 2008, 375-384.
• Wiseman, T., & Yilankaya, O. (2001). Cooperation, Secret Handshakes, and Imitation in the Prisoners' Dilemma: Games and Economic Behavior Vol 37(1) Oct 2001, 216-242.
• Woerdman, E. (2000). Rationality and stability in the Theory of Moves: The case of the Prisoner's Dilemma: Rationality and Society Vol 12(1) Feb 2000, 67-86.
• Wolf, G. (1972). Behavioral processes in different minimal social situations: Comparative Group Studies Vol 3(3) Aug 1972, 221-239.
• Wong, R. Y.-m., & Hong, Y.-y. (2005). Dynamic Influences of Culture on Cooperation in the Prisoner's Dilemma: Psychological Science Vol 16(6) Jun 2005, 429-434.
• Wu, J., & Axelrod, R. (1995). How to cope with noise in the iterated prisoner's dilemma: Journal of Conflict Resolution Vol 39(1) Mar 1995, 183-189.
• Yabuuchi, M. (1986). Metagame theory and extension of conditional strategy in Prisoner's Dilemma game: Japanese Journal of Experimental Social Psychology Vol 26(1) Aug 1986, 57-65.
• Yamagishi, T., Kanazawa, S., Mashima, R., & Terai, S. (2005). Separating trust from cooperation in a dynamic relationship: Prisoner's Dilemma with variable dependence: Rationality and Society Vol 17(3) Aug 2005, 275-308.
• Yamagishi, T., & Kiyonari, T. (2000). The group as the container of generalized reciprocity: Social Psychology Quarterly Vol 63(2) Jun 2000, 116-132.
• Yamagishi, T., Makimura, Y., Foddy, M., Matsuda, M., Kiyonari, T., & Platow, M. J. (2005). Comparisons of Australians and Japanese on group-based cooperation: Asian Journal of Social Psychology Vol 8(2) Aug 2005, 173-190.
• Yamagishi, T., Terai, S., Kiyonari, T., Mifune, N., & Kanazawa, S. (2007). The social exchange heuristic: Managing errors in social exchange: Rationality and Society Vol 19(3) Aug 2007, 259-291.
• Yamauchi, T. (1982). The effect of face-to-face playing on choice behavior in Prisoner's Dilemma game: Japanese Journal of Psychology Vol 52(6) Feb 1982, 337-343.
• Yi, R., Buchhalter, A. R., Gatchalian, K. M., & Bickel, W. K. (2007). The relationship between temporal discounting and the prisoner's dilemma game in intranasal abusers of prescription opioids: Drug and Alcohol Dependence Vol 87(1) Feb 2007, 94-97.
• Yi, R., Johnson, M. W., & Bickel, W. K. (2005). Relationship between cooperation in an iterated prisoner's dilemma game and the discounting of hypothetical outcomes: Learning & Behavior Vol 33(3) Aug 2005, 324-336.
• Yi, R., & Rachlin, H. (2004). Contingencies of reinforcement in a five-person prisoner's dilemma: Journal of the Experimental Analysis of Behavior Vol 82(2) Sep 2004, 161-176.
• Yoshida, F. (1978). An experimental study of interpersonal perceptions in social interaction: I. The cooperator and the noncooperator: Divergent vs convergent perceptions: Japanese Journal of Experimental Social Psychology Vol 18(1) Aug 1978, 11-20.
• Yoshida, F. (1984). Intergroup orientations and intergroup perceptions in a Prisoner's Dilemma Game: Japanese Journal of Psychology Vol 55(5) Dec 1984, 282-288.
• Yoshida, F., & Ohmoto, S. (1985). Comparison between interpersonal and intergroup behaviors and perceptions in a Prisoner's Dilemma Game: Japanese Journal of Psychology Vol 56(2) Jun 1985, 86-92.
• Youngs, G. A. (1986). Patterns of threat and punishment reciprocity in a conflict setting: Journal of Personality and Social Psychology Vol 51(3) Sep 1986, 541-546.
• Zhong, C.-B., Loewenstein, J., & Murnighan, J. K. (2007). Speaking the same language: The cooperative effects of labeling in the prisoner's dilemma: Journal of Conflict Resolution Vol 51(3) Jun 2007, 431-456.
• Zoltan, J. (1992). The effect of recessivity and segregation in the frame of the prisoner's dilemma: Pszichologia: Az MTA Pszichologiai Intezetenek folyoirata Vol 12(4) 1992, 539-564.

### DissertationsEdit

• Acevedo, M. (2002). The effects of social projection and payoff on cooperative behavior in the prisoner's dilemma. Dissertation Abstracts International: Section B: The Sciences and Engineering.
• Armstrong, S. H. (1975). A three-dimensional theory of group process in adolescent dyads: Dissertation Abstracts International.
• Beale, D. K. (1974). Conflicting motives in the Prisoner's Dilemma game: Dissertation Abstracts International.
• Beyer, R. A. (1981). An assessment of the effects of moral level and age on contract maintenance in prisoner's dilemma: Dissertation Abstracts International.
• Bryant, W. P. (1978). Machiavellianism, perspective taking, and partner's response as predictors of interpersonal behavior measured by a modified Prisoner's Dilemma game: Dissertation Abstracts International.
• Charlton, S. R. (2007). The relationship between behavioral measures of self-control: Temporal discounting and the single-player iterated prisoner's dilemma. Dissertation Abstracts International: Section B: The Sciences and Engineering.
• Christensen, R. L. (1976). An investigation of interpersonal trust and the effect of dogmatism and characteristics of the other person on subjective trust in the Prisoner's Dilemma game: Dissertation Abstracts International.
• Conklin, M. M. (1983). An investigation of delinquent and nondelinquent adolescent performance on The Prisoner's Dilemma Game when paired with an adult confederate under three different strategy conditions: Dissertation Abstracts International.
• Elliott, S. W. (1992). Steps towards a psychological calculus for game theory: Application of a model of categorization to the repeated prisoner's dilemma: Dissertation Abstracts International.
• Finney, P. D. (1977). Responsibility attributions and the self system: Dissertation Abstracts International.
• Foster, M. S. (1976). Sex differences in behavior as a function of experience and expectation: Dissertation Abstracts International.
• Hamburger, F. M. (1976). On behavioral effects of normative and attitudinal communications: Dissertation Abstracts International.
• Harkey, S. T. (2001). Choice propensity in single exposure/no-feedback prisoner dilemmas as a function of social orientation, payoffs, and expectations: Evaluation of a formal model. Dissertation Abstracts International: Section B: The Sciences and Engineering.
• Hartman, E. A. (1973). The motivational basis of sex differences in the Prisoner's Dilemma game: Dissertation Abstracts International Vol.
• Helm, B. L. (1973). Locus of control and the exercise of coercive power: Dissertation Abstracts International.
• Herrman, K. D. (2006). Inducing interpersonal trust and team learning using a prisoner's dilemma game. Dissertation Abstracts International: Section B: The Sciences and Engineering.
• Hoerl, R. T. (1972). Cooperation and competition as a function of communication and trust: Dissertation Abstracts International Vol.
• Jacobs, M. K. (1976). Women's moral reasoning and behavior in Prisoner's Dilemma: Dissertation Abstracts International.
• Kimmel, M. J. (1975). On distinguishing interpersonal trust from cooperative responding in the Prisoner's Dilemma game: Dissertation Abstracts International.
• Koenig, K. K. (1980). Cooperation as a function of locus of control in a Prisoner's Dilemma game: Dissertation Abstracts International.
• Krause, R. M. (1975). A general conflict simulation model for ecological generality using the Prisoner's Dilemma: Dissertation Abstracts International.
• Lichtig, L. K. (1977). The development of interpersonal relationships: An experimental approach: Dissertation Abstracts International.
• Lopez, L. C. (1977). The relationship between selected cognitive styles and cooperation in a Prisoner's Dilemma game situation: Dissertation Abstracts International.
• Mayer, F. J. (1993). Nonlinear dynamics of strategic interactions: Dissertation Abstracts International.
• McCarter, R. H. (1988). Self-integration and self-defeating behavior in the Prisoner's Dilemma Game: Dissertation Abstracts International.
• Morikawa, T. (1994). A cognitive theory of how cooperation evolves: A simulation. Dissertation Abstracts International Section A: Humanities and Social Sciences.
• Oman, R. N. (1978). The effect of unpredictable and malevolent strategies on the game playing of childhood schizophrenics: Dissertation Abstracts International.
• O'Riordan, N. F. (1987). Behavior of low and high trust juvenile delinquents when playing a modified Prisoner's Dilemma Game: Dissertation Abstracts International.
• Pincus, J. (1977). Cognitive factors and cooperation in the Prisoner's Dilemma: Dissertation Abstracts International.
• Pivnick, W. P. (1973). Parental occupation and situational meaning as determinants of behavior in the Prisoner's Dilemma Game: Dissertation Abstracts International Vol.
• Plous, S. L. (1986). Perceptual illusions and military realities: A social-psychological analysis of the nuclear arms race: Dissertation Abstracts International.
• Pollard, S. W. (1975). Effects of power on cooperation: Dissertation Abstracts International.
• Romero, C. (1978). Cooperative behavior of prison inmates towards peers and institutional staff utilizing the prisoner dilemma game: Dissertation Abstracts International.
• Sachteleben, T. L. (2006). The effect of opportunity cost, level of cooperation, and social value orientation on preferences for structural solutions to the N-person Prisoner's Dilemma. Dissertation Abstracts International: Section B: The Sciences and Engineering.
• Sanabria, F. (2004). Pigeons in an operant prisoner's dilemma: New experimental paradigms. Dissertation Abstracts International: Section B: The Sciences and Engineering.
• Sell, R. L. (1977). Cooperation and competition as a function of residential environment, consequences of game strategy choices and perceived control: Dissertation Abstracts International.
• Setzman, E. J. (1974). Cooperation and competition between men and women in a dyadic game-playing situation: Dissertation Abstracts International.
• Shebalin, P. V. (1997). Collective learning and cooperation between intelligent software agents: A study of artificial personality and behavior in autonomous agents playing the infinitely repeated prisoner's dilemma game. Dissertation Abstracts International: Section B: The Sciences and Engineering.
• Speyer, E. C. (1985). Trust level within a dyad as influenced by observed trust level of a more powerful person without and within the dyad during the Prisoner's Dilemma Game: Dissertation Abstracts International.
• Stahelski, A. J. (1981). The interaction of cooperators and competitors in a conversational simulation of the Prisoners Dilemma game: Dissertation Abstracts International.
• Stuart, H. W. (1993). Non-equilibrium and non-procedural approaches to game theory: Dissertation Abstracts International.
• Swan, G. A. (1974). Machiavellianism, impulsivity, field dependence-independence, and performance on the Prisoners' Dilemma game: Dissertation Abstracts International.
• Talley, M. B. (1975). Effects of asymmetry of payoff and asymmetry of information in a Prisoner's Dilemma game: Dissertation Abstracts International.
• Tempey, D. F. (1975). Trust, choice behavior, and activity description: Dissertation Abstracts International.
• Ugis-Upton, T. A. (1981). An investigation of the effectiveness of the communication of confession of guilt and restitution on the reduction of distrust: Dissertation Abstracts International.
• Whitehill, M. B. (1987). Psychopathy and interpersonal relationships: Dissertation Abstracts International.
• Widom, C. S. (1974). Interpersonal conflict and cooperation in psychopaths: Dissertation Abstracts International.
• Winkel, M. H. (1983). Effects of situational, attitudinal, and mediational factors on cooperative behavior: Dissertation Abstracts International.
• Winquist, J. R. (2001). Sources of the discontinuity effect: Being in a group, playing against a group, and between-sides communication. Dissertation Abstracts International: Section B: The Sciences and Engineering.
• Wright, T. L. (1972). Situational and personality parameters of interpersonal trust in a modified Prisoner's Dilemma game: Dissertation Abstracts International Vol.
• Yi, R. (2003). A modified tit-for-tat strategy in a 5-person prisoner's dilemma. Dissertation Abstracts International: Section B: The Sciences and Engineering.