My own strategy-if i'd felt like joining-would have started by checking the opponent against defectbot; anybody who cooperates with even one of the 5 or so defect-varaints is clearly insane and not to be trusted; defect immediately. OR maybe take a detour and check if they're actually a mimicbot that got unlucky.

well...I might have played Hawkbot instead; Hawkbot spends 9.999 seconds dithering before finally defecting, so it does insanely well against any opponent that tries to run it.

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Quinn appears to have submitted something similar. As far as I can tell, against CooperateBot it cooperates; otherwise, it waits 9 seconds before defecting. (The weird timing conditional in there should never return true if things are working properly, and checking the results, indeed, it defected against everything but the three CooperateBots.)

0wedrifid7yAnybody who runs the other program without an interrupt timer and so times out is, as you put it, "clearly insane". Hawkbot gets 1 against any sane opponent that tries to run it.
0Luke_A_Somers7yThat wouldn't work well since timing out causes both players to get 0. You'd do better just defecting.

Prisoner's dilemma tournament results

by AlexMennen 1 min read9th Jul 2013124 comments


The prisoner's dilemma tournament is over. There were a total of 21 entries. The winner is Margaret Sy, with a total of 39 points. 2nd and 3rd place go to rpglover64 and THE BLACK KNIGHT, with scores of 38 and 36 points respectively. There were some fairly intricate strategies in the tournament, but all three of these top scorers submitted programs that completely ignored the source code of the other player and acted randomly, with the winner having a bias towards defecting.

You can download a chart describing the outcomes here, and the source codes for the entries can be downloaded here.

I represented each submission with a single letter while running the tournament. Here is a directory of the entries, along with their scores: (some people gave me a term to refer to the player by, while others gave me a term to refer to the program. I went with whatever they gave me, and if they gave me both, I put the player first and then the program)

A: rpglover64 (38)
B: Watson Ladd (27)
D: skepsci (24)
E: Devin Bayer (30)
F: Billy, Mimic-- (27)
G: itaibn (34)
H: CooperateBot (24)
I: Sean Nolan (28)
J: oaz (26)
K: selbram (34)
L: Alexei (25)
M: LEmma (25)
N: BloodyShrimp (34)
O: caa (32)
P: nshepperd (25)
Q: Margaret Sy (39)
R: So8res, NateBot (33)
S: Quinn (33)
T: HonoreDB (23)
U: SlappedTogetherAtTheLastMinuteBot (20)