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'Tit for Tat' Defeated In Prisoner's Dilemma Challenge

colonist writes "Tit for Tat, the reigning champion of the Iterated Prisoner's Dilemma Competition, has been defeated by a group of cooperating programs from the University of Southampton. The Prisoner's Dilemma is a game with two players and two possible moves: cooperate or defect. If the two players cooperate, they both have small wins. If one player cooperates and the other defects, the cooperator has a big loss and the defector has a big win. If both players defect, they both have small losses. Tit for Tat cooperates in the first round and imitates its opponent's previous move for the rest of the game. Tit for Tat is similar to the Mutual Assured Destruction strategy used by the two nuclear superpowers during the Cold War. Southampton's programs executed a known series of 5 to 10 moves which allowed them to recognize each other. After recognition, the two Southampton programs became 'master and slave': one program would keep defecting and the other would keep cooperating. If a Southampton program determined that another program was non-Southampton, it would defect." Update: 10/14 15:08 GMT by J : If anyone wants to try writing their own PD strategy and see how it fares in a Darwinian contest, I'll host a tournament of Slashdot readers. Here are the docs, sample code, notes on previous runs, and my email address.

13 of 356 comments (clear)

  1. Scary Stuff by mfh · · Score: 5, Funny
    FTA:
    • If you confess and your partner denies taking part in the crime, you go free and your partner goes to prison for five years.
    • If your partner confesses and you deny participating in the crime, you go to prison for five years and yor [sic] partner goes free.
    • If you both confess you will serve four years each.
    • If you both deny taking part in the crime, you both go to prison for two years.
    This sounds pretty much like the RIAA might be involved. I would deny everything if I were you!
    --
    The dangers of knowledge trigger emotional distress in human beings.
  2. That's why... by Stile+65 · · Score: 4, Funny

    ...fraternities and secret societies work so well!

    I'm off to join the Freemasons. Be back in a few.

    --
    I claim first use of "Error No. 0B" - or "No. 0B error." It'll be the new ID 10T!
  3. Practicality by Perianwyr+Stormcrow · · Score: 2, Funny

    I generally hope that knowledge of the prisoner's dilemma will never become a practical factor in my life.

    --

    What we call folk wisdom is often no more than a kind of expedient stupidity.-Edward Abbey

  4. only thing I can say is... by jjeffries · · Score: 3, Funny
    HOW ABOUT A NICE GAME OF CHESS?

    Lameness filter encountered. Post aborted!
    Reason: Don't use so many caps. It's like YELLING. It's not at all like a TALKING COMPUTER. You are a bad man. Go away.

    1. Re:only thing I can say is... by cHALiTO · · Score: 1, Funny

      Clearly, the only winning move is not to play :)

      --
      "Luck is my middle name," said Rincewind, indistinctly. "Mind you, my first name is Bad." -- Terry Pratchett
    2. Re:only thing I can say is... by OptimizedPrime · · Score: 2, Funny

      So what you're saying is my algorythm won this year since I kept it written on a post it on my desk instead of submitting it?

  5. Tit for Tat by alexo · · Score: 4, Funny

    Why should Tat get all the fun?

  6. Re:That's not really so special by Minwee · · Score: 4, Funny

    I was with you up until you started talking about tits and S/M... Am I still on slashdot, or did I wander onto alt.com by mistake?

  7. Re:That's not really so special by Anonymous Coward · · Score: 0, Funny

    "Am I still on slashdot?"

    Well, you made an lame attempt at humor without spending the two seconds required to read the post and summary and comprehend them.

    So, yes, you are still on Slashdot.

  8. Re:...by cheating! by wo1verin3 · · Score: 2, Funny

    See I was trying to bring a supergrape in to play against my grandfather and he didn't believe me.. thank god i have someone to back me up now!

  9. Wait a Minute! by Waffle+Iron · · Score: 2, Funny
    What I want to know is:
    What is tat?
    Where do I get it?
    And how do I exchange it for the other thing?

    --Dennis Miller (IIRC)

  10. new exploit? by An+ominous+Cow+art · · Score: 2, Funny

    Curse these researchers, now black hats will be using this technique to let exploit code escape from chroot prisons!

  11. sed for the rescue by alexo · · Score: 2, Funny
    > Hell, I've got a whole warehouse full of Tat. Where do I exchange it for some tit?

    Easy:
    s/wa/who