The secret to winning at rock, paper, scissors | Hacker News Reader

The secret to winning at rock, paper, scissors

telegraph.co.uk

23 pointsnickb19 comments

Well now everyone knows that rock is the most popular (suggesting you should throw paper), meaning scissors is the best way to start, the smart money will move to throwing rock, which of course means the really smart will start with paper, so to really get the edge you throw scissors. No, wait...

Unfortunately the NS source article is paywalled, so we miss the part where they give the (probably small) improvement in odds that scissors (currently) gives.

The interesting part about RPS for me is the evolutionary/ecological/game-theoretical implications, "Some of the male lizards (call their type "rock") use force, invading the territory of fellow males to mate with females. Others ("paper") favor deception, waiting until females are unguarded and sneaking in. Still others ("scissors") work by cooperation, joining together to protect one another's females. The three types of lizard... are locked in a cyclical sort of standoff. "

[http://www.nytimes.com/2007/12/09/magazine/09rockpaper.html?...]

Also: [http://www.sciencedaily.com/releases/2007/10/071001145022.ht...]

And this is one of the main reasons why you see thinly disguised RPS game mechanics in most strategy games, esp. multiplayer online games. Cycles of pwn are the easiest way to prevent absolutely optimal strategies (the I Win Button syndrome).

You want to check out Game Theory Evolving, by Herbert Gintis, if you haven't already. It talks about exactly this kind of stuff.

Looks interesting, thanks!

Interestingly enough, I played in the World Series of Roshambo a couple years back. In the second round I put what Gavin Smith calls the worst beat in the history of the sport on him. It was best of seven, and he got me down 3-0. On the fourth throw I balked, which is a permissible stall tactic. After that I had a feeling he was going rock, so I threw paper. The same happened for the next three throws and I moved on to the next round.

I've been told by a few people that if you look very closely, you can see me throwing paper on the ESPN coverage.

I just look at my watch and take the seconds mod 3. 0:rock, 1:paper, 2:scissors. Pretty sure random play (insofar as this method is random) is best.

That's optimal only if your opponents also act randomly. (Or in the absence of any information.)

>That's optimal only if your opponents also act randomly.

By choosing the random strategy you force your opponent to do the same and you have a draw. It is optimal, in this sense.

Funny, I always use (seconds+1)%3...

That's the strategy I use while playing against jsomers, but while playing against chengmi, I always use (seconds+2)%3. (Unfortunately, chengmi's watch is 2 seconds fast (or 1 second slow), so he still ends up winning...)

Psshh.. I make all of my rock-paper-scissors decisions with a resistance noise generator.

> Alternatively you could throw the move that would have beaten your opponent's previous move. The logic here is that players subconsciously try to beat their own previous move.

Wouldn't that mean you should throw the move that beats the move that would have beaten the opponents previous move?

This line of thinking happens in high level rock paper scissors. You need to predict exactly how many levels deep your opponent is going. Professional RPS players will often throw six or seven doubles in a row before someone wins.

See this 200 page guide for more info than you will ever want to read: http://www.scribd.com/doc/924991/The-Official-Rock-Paper-Sci...

emfle is making a more straightforward point: if you anticipate your opponent will try to beat his latest move, you should not try to beat his latest move too; that would be shooting for a draw.

"That means that your opponent is likely to choose paper, because they will expect to you to start the game with stone."

So because stone is the most likely move, paper is the most likely move? Funky logic...

I think what they meant was that most people "think" that rock is the most likely move and therefore choose paper.

http://www.deepsblog.com/2007/08/29/world-war-ii-rock-paper-...

http://worldrps.com/

I've personally had pretty good success with the crescendo.

Man, I really hate pop science. What will those crazy scientists do next!

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