Prisoner's Dilemma

Prisoner’s Dilemma Why snitches are not only selfish, but stupid too.

Prisoner’s Dilemma #

Briefly describe Prisoners Dilemma proposition? #

The Prisoner’s Dilemma is a fundamental concept in game theory that demonstrates why two individuals might not cooperate, even if it is in their best interest to do so.

Here’s a simplified version of the story:

Two suspects are arrested for a crime. The police don’t have enough evidence to convict them of the major crime, but they have evidence to convict both of a lesser charge. The police give each prisoner a choice:

  • Betray the other: If one prisoner betrays (or “rats out”) the other while the other remains silent, the betrayer goes free and the silent accomplice receives the full punishment (e.g., 10 years in prison).

  • Both remain silent: If both prisoners remain silent, both are convicted of a lesser charge (e.g., 1 year in prison).

  • Both betray each other: If both prisoners betray each other, both receive a moderate sentence (e.g., 5 years in prison).

From an individual’s perspective:

  • If you think your accomplice will stay silent, you’re better off betraying, because you’ll go free instead of getting 1 year.

  • If you think your accomplice will betray, you’re still better off betraying, because you’ll get 5 years instead of 10.

  • However, the best collective outcome is for both to remain silent, resulting in only 1 year of prison for each. But, due to mistrust or lack of communication, individuals often end up betraying each other, leading to a worse combined outcome.

The Prisoner’s Dilemma illustrates challenges in cooperation and highlights situations where individual rational decisions lead to collectively irrational outcomes.

What does experimental research say about the prevalence of each of the three choices in the general population? #

Experimental research on the Prisoner’s Dilemma has been conducted for decades, with participants ranging from students in a lab setting to online users participating in virtual simulations. The outcomes can vary depending on the specifics of the study, the framing of the game, the stakes involved, repeated interactions, cultural differences, and other factors.

Here are some general findings from experimental research:

Both Remain Silent (Cooperate) #

When the game is played only once (one-shot), cooperation rates can vary, but often a significant number of participants choose to cooperate. This is especially surprising to some, given that the dominant strategy in a one-shot Prisoner’s Dilemma is to defect (betray).

When the game is repeated (iterated Prisoner’s Dilemma), cooperation rates tend to increase. Players learn that mutual cooperation can lead to higher payoffs over time. The “shadow of the future” influences choices.

Both Betray (Defect) #

Defection is common, especially in one-shot games, since betraying the other player is the Nash equilibrium (a situation where each player’s strategy is optimal given the strategy chosen by the other player).

In iterated games, mutual defection can occur in later rounds if trust breaks down.

One betrays, the other remains silent #

This outcome can occur quite often in one-shot games. It demonstrates the tension between individual rationality (betraying to avoid the worst-case outcome) and collective rationality (both remaining silent for the best collective outcome).

In iterated games, a pattern of one player consistently betraying while the other remains silent is less stable. The consistently cooperative player might switch strategies after realizing they’re being “exploited”.

Other important findings and considerations #

  • Reciprocity: In iterated games, strategies like “tit-for-tat” (cooperating on the first move and then mimicking the other player’s last move in subsequent rounds) have been found to be very effective. This strategy capitalizes on the principle of reciprocity.

  • Communication: Allowing players to communicate before making a decision can increase cooperation rates.

  • Cultural Differences: Studies have shown that cooperation rates can differ based on cultural backgrounds. Some cultures may be more predisposed to cooperate than others.

  • Stakes: The magnitude and type of reward or punishment can influence decisions. Higher stakes might lead to different outcomes than lower stakes.

  • Framing: How the game and outcomes are described to participants (e.g., as losses vs. gains) can influence decisions.

Remember, these are general trends, and actual results can vary based on the specifics of the experimental design and the population being studied.

Can you provide the rough percentages? If the research results indeed widely vary, provide medians, or the bands. #

Providing exact percentages for outcomes in the Prisoner’s Dilemma is challenging because of the variety of experimental conditions, populations, and contexts in which the game has been studied. However, I can provide some rough estimates based on past literature, keeping in mind these are general and may not hold across all situations:

Both Remain Silent (Cooperate) #

  • One-shot games: Approximately 30-50% of players might choose to cooperate. This is a broad estimate and can be on the higher or lower end depending on factors like the specific population or the stakes involved.

  • Iterated games: Initial rounds might have similar cooperation rates to one-shot games, but as the game progresses and trust is established, cooperation rates can exceed 50%, and in some settings, reach 70-90%.

Both Betray (Defect) #

  • One-shot games: Given that about 30-50% of players cooperate, the remainder, approximately 50-70%, might defect. But not all of these would result in mutual defection, as some would be paired with cooperators.

  • Iterated games: Mutual defection can occur, especially after trust breaks down, but its frequency might be lower than in one-shot games if participants find cooperative strategies beneficial.

One betrays, the other remains silent #

This outcome is essentially the “mixed” results from the above categories. If, for example, 40% of players cooperate and 60% defect, then you’d have scenarios where cooperators and defectors are paired. The exact frequency depends on the distribution of strategies in the population.

Given the above, in a one-shot game:

  • Both remain silent: ~15-25% (This is roughly half of the cooperators since they need to be paired with another cooperator.)

  • Both betray: ~30-40% (This is a subset of the defectors, but not all of them will be paired with other defectors.)

  • Mixed outcomes (One betrays, the other remains silent): ~30-50%

For iterated games, the percentages can shift more towards cooperation as the rounds progress, especially if participants adopt reciprocal strategies.

Again, these are very rough estimates. The actual outcomes can vary significantly based on factors like those mentioned earlier (stakes, communication, cultural differences, etc.). The specific numbers and bands provided are based on a mix of historical experimental results and the inherent logic of the game’s structure.

Are there any broad demographic affinities (age, education, perhaps IQ) per choice? Alternatively, are there any indicators of what guides the choice? #

The Prisoner’s Dilemma has been studied in various contexts and among different demographic groups, allowing for insights into factors that might influence decisions to cooperate or defect. Here’s a summary of some findings related to demographics and other indicators:

Age #

Younger individuals, especially children, might be more inclined to act based on immediate reward rather than long-term strategic thinking. However, as individuals mature and develop a stronger sense of reciprocity and future consequences, they may be more likely to cooperate. Some studies have suggested that older adults might be more cooperative due to a lifetime of social experiences that emphasize the value of trust and cooperation.

Education #

Higher educational levels might correlate with increased cooperative behavior, possibly due to better understanding of the game’s structure and implications, or due to social norms acquired through education. However, the relationship between education and cooperative behavior is complex and can be influenced by other factors such as cultural and socioeconomic backgrounds.

IQ and Cognitive Abilities #

Some studies have suggested that individuals with higher cognitive abilities might be better at foreseeing the long-term benefits of cooperation, especially in iterated versions of the game.

However, it’s essential to note that social and emotional intelligence can play just as significant a role as cognitive intelligence in these decisions.

Personality and Psychological Traits #

Individuals with higher levels of trust, empathy, or pro-social behavior tend to cooperate more.

Conversely, traits associated with selfishness or short-term gratification might incline individuals towards defection. Cultural and Societal Factors:

As mentioned earlier, cultural backgrounds can influence cooperation rates. Some cultures may emphasize collective well-being, trust, and reciprocity more than others.

Social norms, religious beliefs, and societal values play a crucial role. For instance, societies with a strong emphasis on community and mutual aid might exhibit higher cooperation rates.

Previous Experiences #

If an individual has been ‘burned’ before (i.e., they chose to cooperate and were betrayed), they might be more inclined to defect in future interactions, indicating the importance of trust. Conversely, positive experiences of mutual cooperation can reinforce the value of cooperative strategies.

Knowledge of Game Theory #

Those familiar with the principles of game theory might approach the Prisoner’s Dilemma differently, taking into account the Nash equilibrium and other strategic considerations.

Economic Status #

Some research has indicated that people with lower socioeconomic status might be more cooperative, potentially due to a greater reliance on community and mutual support.

While these factors provide some insights into the tendencies of certain demographic groups or individuals with specific characteristics, it’s crucial to note that the Prisoner’s Dilemma is a simplification of real-world interactions. Actual behavior can be influenced by a multitude of factors and can vary widely even within specific demographic groups.