Rock, Scissors, Paper - a classic game brought to the PC


Click here to download the game (windows PC only)


You know how to play this Ė you make your choice, the computer makes its choice and you compare. What could be easier?


In this version, the computer learns as it plays against you. It knows that your optimal strategy is to play at random, yet it also knows that people are not very good random number generators. So the computer looks for patterns in your play that deviate from being random and tries to exploit those differences to improve its score.


The surprising thing is how difficult it is to be random. Just click on your choices rapidly, switching back and forth and let the computer keep score. You will see that the computer beats you most of the time. You have to work a little harder to win.


Can you win against the machine? Certainly, but if you do play optimally, the computer, detecting no patterns in your play, plays randomly and as a result you should only expect to win half of the time. However, whenever you play sub optimally, the computer will see it and exploit it to win more than half of the time.


My father, Eldon, wrote this game and asked that I post it. I have asked him to divulge the inner workings of the code and who knows; maybe heíll get around to it. Since I helped him with the algorithm, I already know how it works. But before he posts the method, see if you can figure out an algorithm that would play for the computer.


If you want it, Iíll even give you a hint.


On the other hand, you can just go straight to Eldonís write up of the Algorithm.