Submit a complete technical report on a project about the Iterated Prisoners’ Dilemma that will be presented during the class.

• Three strategies analyzed:
  • ALL-D: always defect, optimizes individual fitness
  • ALL-C: always cooperate, optimizes population fitness
  • RAND: randomly chooses between defect and cooperate
• Expected scores from this analysis:

• Uses a darwinism model
• Each entity has a fitness function
• Each generation selects the most fit individuals to reproduce
• Each reproduction produces a new generation with some mutations, traits of predecessors MUST be passed on
• Over time, the population will evolve to be more fit

• Population of 100 individuals
• Chromosome is a 64-bit string representing the strategy of the individual
• A bit is a choice depending on cooperate or defect played for a specific configuration of past moves

How do you encode a strategy with a string?

Suppose memory depth is only 1. Then, there are only four choices, based on previous moves:

Now, using 3 previous moves, suppose the memory is this:

(RTR = 010 = 5) (I don't get this part but we can just use opponent moves probably)

** Bit string must be 2 ** MEMLEN + MEMLEN long; last MEMLEN bits are reserved for the first few moves.

• Fitness: Each player competes against every other for 64 consecutive rounds, and a cumulative score is maintained
• Selection: Roulette Wheel selection
• Reproduction: Random point crossover with replacement
• Mutation rate 0.001
• Generations: 1,000 generations

• Tit for tat (TFT)
  • First move, cooperate
  • Always choose opponent's last move as next move
• Tit for Two Tat (TFT2)
  • First two moves, cooperate
  • If the opponent defects twice in a row, choose defection as the next move
• Suspicious Tit for Tat (STFT)
  • First move, defect
  • Always choose opponent's last move as next move
• Free Rider (ALL-D)
  • ALWAYS defect
• Always Cooperate (ALL-C)
  • Must I say any more

You will form groups of 3 or 4.

• Abstract (150-200 words summarizing your work and highlight your findings)
• Introduction (general overview, motivation, your contribution)
• Relevant Literature Review
• Experimental setup and methodology, discussion of your findings
• Concluding remarks with a brief future work section
• References
• Appendix containing all extra materials used