Lecture 13 - Cooperation II

Question 1

What is the condition for a game to be a prisoner’s dilemma game?

Answer 1

Temptation MORE THAN reward MORE THAN punishment MORE THAN sucker

Question 2

Is cooperating or defecting the evolutionary stable strategy?

Answer 2

Defecting

Question 3

What is the condition for a game to be a snowdrift game?

Answer 3

Temptation MORE THAN reward MORE THAN sucker MORE THAN punishment

Question 4

What is the evolutionary stable state in a snowdrift game?

Answer 4

A mixed state

Question 5

In a snowdrift game, what should happen as the cost increases (relative to the benefit)?

Answer 5

The proportion of cooperators in the population should fall.

Question 6

What is the Iterated Prisoner’s Dilemma?

Answer 6

A single game with a given number of rounds, allowing individuals to react to an opponent’s past behaviour.

Question 7

What is a Spatial Prisoner’s Dilemma?

Answer 7

Players interact with their neighbours.

Question 8

What is a Continuous Prisoner’s Dilemma?

Answer 8

Instead of all or nothing strategies, cooperation varies continuously.

Question 9

What is reciprocation?

Answer 9

Giving back / returning a favour

Question 10

What is reciprocal altruism?

Answer 10

To stop cooperation in the first instance of non-cooperation and remain non-cooperative.

Question 11

Give some mechanisms that promote cooperation.

Answer 11

• Reciprocation
• Punishment/retribution
• Policing

Question 12

Give an example of retribution promoting cooperation.

Answer 12

• Turkana, a society in East Africa
• Raiding parties comprised of few hundred warriors, participants not kin
• Cowardice and desertions punished by community-imposed sanctions, promoting cooperation among raiding parties

Question 13

Give an example of policing promoting cooperation.

Answer 13

Workers lay unfertilised eggs (would develop into haploid males).
Almost all policed before hatching and eaten by other workers, gain more in inclusive fitness from raising queen’s sons.