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Rock-Paper-Scissors

emmett posted more than 14 years ago | from the one-two-three-shoot dept.

Programming 136

Andreas Junghanns writes: "Check out the Second International RoShamBo Programming Competition for a completely different experience! If you think you know everything about Rock-Paper-Scissors -- here is your chance to prove it against some stiff international competition. At the Web site you can find rules, sample programs and a report of the first contest, complete with results and program descriptions." This looks pretty cool, and it might make a neat first project for someone, too.

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OFFTOPIC: Infinite Monkeys (1)

dagoalieman (198402) | more than 14 years ago | (#993631)

Obviously, we let them back out of the cage when we opened this topic up. That I have no problem with.

However, for the sake of the moderators that we have here, it seems that many of them have grown hostile since the last time we dropped a football around them. The one with the football is still swinging from the goalposts, the normal monkeys are at the keyboards, but the rest (of the infinite, somehow) are lining up with their rocket launchers, chainsaws, and rail guns to post here.

Please, people, drop the hostility, and use email flames if anything to shut people up. If you need to be an anonymous coward, use a hotmail account. Otherwise <rant mode> SHUT THE HELL UP!</rant mode>.

Thank you. Someone please cage the monkeys again soon, as someone has to clean up their crap...

And now a word from our Sponsors (1)

TimeHorse (6545) | more than 14 years ago | (#993633)

This year's RoShamBo competation is funded in part with thanks to The Movellan Society for the Total Eradication of the Dalek Scourge from the Entire Universe (MSTEDSEU).

I thought ... (1)

tilleyrw (56427) | more than 14 years ago | (#993634)

RoShamBo was a game where one player kicks the other player in the nuts as hard as they can, then the other player kicks, and it goes back and forth until one player falls down.

Courtesy Eric Cartman

Well... it sounded like a good idea (1)

ka9dgx (72702) | more than 14 years ago | (#993635)

I really thought it might be fun... until I found out that the submission had to be in 'C'. I could do this as a MS-DOS program in Turbo Pascal, or in Delphi under Windows, or even as a CGI program under IIS... but since they don't support a universal platform, I'm out. 8(

--Mike--

Re:This Must Be More Complex Than It Sounds . . . (1)

EvilSoloman (95354) | more than 14 years ago | (#993636)

Most people will probably include some analysis code, and may "bend" probability if the opponent seems particularly redundent.

However, if you have a contestant which analyzes the opponent's strategy, you can also have one which deliberately tries to trick that software - feint a pattern, then switch to a counter-strategy based on what the opponent is likely to respond with.

For example, one could choose Rock, Paper, Scissors in that order twice, and then the opponent program would sense that it's more likely that you'd choose Rock on the next move - therefore, it would respond with Paper, and you would cut it to pieces with Scissors!

Ah i'm insane anyway.

More Traditional Karma Whoring (1)

grammar nazi (197303) | more than 14 years ago | (#993637)

the Roshambo Ten Commandments:

I am the Lord your rock. Thou shalt make no paper to cover me.

Thou shalt not covet thy neighbor's paper.

Thou shalt not cheat at cards.

Paper covers rock, rock crushes scissors, scissors cuts paper; all other combinations shall be a "push."

Keep thy circles below thy waist.

Thou shalt wipe thy victim's arm after thou puncheth his shoulder.

Going rock all the time is NOT good; SAYING you are going rock every time may be.

Keep the Wednesday night sacred, for it is the day on which poker shall be played.

To be tilted is a admirable state, but to angle is divine.

The holiest of pilgrimages is to Vegas. Thou who doest remain at home shall be a "pussy."

I'm not taking credit for this one, go here [emf.net] .

RPS - Alife tactics (1)

The Silicon Sorceror (40289) | more than 14 years ago | (#993638)

It would be interesting to apply the evolutionary theories behind Core Wars and many other artificial life programs to RPS programs. The way these work is that some basic "starter" programs written in a synthetic language are pitted against each other virtually. The losers from this round are eliminated, and the gaps are filled with mutated copies of the survivor programs. Continue this ad nauseum, and you get some pretty good programs. Of course, it would take quite a few rounds to end up with a program with some really good AI, but this would be an interesting project.

Re:Traditional Karma Whoring (1)

$lacker (127735) | more than 14 years ago | (#993639)

Yeah, see, Signal knows how it's done. You wanna know how to karma whore? You go to him. Kid knows all the ins and outs

It is.... (3)

Anonymous Coward | more than 14 years ago | (#993640)

From someone who has spent about 1 week of his life trying to come up with a startegy to win, I can tell you it is quite difficult. My strategy was to have three variables, each corresponding to the three possible moves - rock, paper or scissor. Then follow the rules below to come up with a move.
  • Choose a random move. Add one to that move.
  • Check if opponent is making same move all the time. Add one to the move that will beat that.
  • Check if opponent is moving in a cyclic pattern. Add one to the move that will beat that.
  • Check if opponent is trying to beat my last move. Add one...
  • Check if opponent is trying to beat the move that I would have played if I wanted to beat it the last turn. Add one...
  • If I've been losing a lot lately, make a random move, otherwise make the move that has the highest count.

These strategies all together easily beat the sample bots but get hammered by the competitive bots. They are no where near as powerful as the competitive bots. I was going to do a bit more extensive pattern matching routines to try and beat them, but just havent got around to doing it.

Vivek Mittal Telstra Research Labs

PS: I wonder how much my first post ever on /. will get moderated. :)

PPS: Can we add another way to get your account information back... enter email... I dont remember by user id and when I try to create a new account, /. complains of a duplicate email.

There is a real strategy to be found (1)

psm (105737) | more than 14 years ago | (#993641)

Why bother with analysis of your opponent's approach. I think the real way to tackle this would be to already know your opponent's tactics. You can do this by submitting heaps of "different" entries to the competition (not sure if this is valid as the site seems to be /.'d), and since you then have a good chance of coming up against a program you have written, you could easily beat it!

That's sure to get you through a few rounds at least :)

has already been done.... (2)

Anonymous Coward | more than 14 years ago | (#993642)

Somewhere on the web site they has a section of cheating bots and one of the bots did exactly that. It somehow re-engineered the RNG and won all 1000 times against the random bot. Vivek Mittal Telstra Research Labs

Re:This Must Be More Complex Than It Sounds . . . (1)

Kyobu (12511) | more than 14 years ago | (#993643)

No, there are not three variables. There is one (external) variable, the result. That variable has three possible values, Rock, Paper, or Scissors.

I won the last year's competition -- here's how... (5)

egnor (14038) | more than 14 years ago | (#993644)

My submission, Iocaine Powder [ofb.net] , won last year's competition. Follow the link to see a complete description of how it works. The competition results [ualberta.ca] from last year describe some of the other strategies that did well (and some that did not-so-well).

This competition is more complex than it seems; not only are there deliberate "dumb robots", but many of the real entries are quite predictable. A random player wouldn't have made it close to winning, and stalemates were rare.

What does this year hold in store? We'll just have to see!

Good ole rock. (1)

AgentRavyn (142623) | more than 14 years ago | (#993645)

Gotta love that Simpson's episode:

Bart: Good ole rock. Nuthin beats rock.

___
A requirement of creativity is that it contributes
to change. Creativity keeps the creator alive.

Typical of Slashdot to glorify violence (4)

Anonymous Coward | more than 14 years ago | (#993646)

I'm really not suprised that all you gun-toting, neo-nazi Americans would try to glorify some excessively violent childhood game like Rock Paper Scissors. Have any of you stopped to consider what these sorts of values these pasttimes instill in our children?

I mean, let's start with the rock. And I'm not refering to that movie with Nicholas Cage & Sean Connery in it, either. Rocks == Violence! Ask any caveman! Were it not for Oog being silenced by the Lameness Filter, I assure you he would back me up on this.

As for the scissors, well why don't you just throw children off a cliff? How many times have we been told not to run with scissors, and here /. is urging people to use them as both toys and weapons!

And the paper... oh Lord, how irresponsible can you get? We do all we can to squash that horrible "Puff the Magic Dragon" degenerate druggy song and then you people come along and start handing out Zig Zag's to elementary school students!

While we're at it, let's review the "premise" of this whole "game":

  • Rocks violently destroy scissors
  • Scissors violently slice apart paper
  • Paper violently smothers the helpless rock

Are any of you thinking about the children? I seriously doubt it!

Two things (3)

luge (4808) | more than 14 years ago | (#993647)

1) AI class I took last year (well, TA'd) we went in to some detail on possible RPS strategies. Yes, you can have strategies, at least assuming that your opponent is not a pure RNG (in which case the only correct strategy is to be RNG yourself.)
2) Nothing that the tourney produces will be as cool as this [duke.edu] . Unfortunately, the picture stinks, but on the left is my professor, and on the right is the kid (he'll hate me for that) who build the RPS-playing Lego Mindstorm. And that's the RPS bot in the kid's hand. It used some pattern learning software (written in legOS [sourceforge.net] ) to attempt to detect patterns in human RPS players. Didn't work great, but what the heck... it was still damn cool. Had fingers and the whole bit.
~luge

Re:I won the last year's competition -- here's how (1)

Gill Bates (88647) | more than 14 years ago | (#993648)

So, how does Iocaine Powder perform against itself? Have you done this analysis?

Re:Play Rock, Paper, Scissors over the phone (1)

Royster (16042) | more than 14 years ago | (#993649)

In order to view the source, etc. you need to get a free login of their "developer studio" - but if you don't want to do that, here's how to play:

In a futile attempt to maximize karma, eries [slashdot.org] perpetrated the first Slashdotting of a PBX.

Re:Here's My Entry (1)

DotWarner (56614) | more than 14 years ago | (#993650)

I suspect that this will work better than you'd think. An intelligent entry will assume that nobody is stupid enough to play the same thing every single time, and will assume at some point that you're faking it out and try to outsmart you by playing scissors. A simpler program that plays the averages will win at least 999 times, but more complicated programs may handle it less effectively.

Re:Rock Paper Scisors expansion kits... (1)

ktakki (64573) | more than 14 years ago | (#993651)

Damn, Seebs. You're weird.

k.

--
"In spite of everything, I still believe that people
are really good at heart." - Anne Frank

Hmm... (2)

PurpleBob (63566) | more than 14 years ago | (#993652)

... and for the sequel, a Tic-Tac-Toe robot competition!

Actually, I never realized there were so many levels of depth to Rock-Paper-Scissors. Neat.
--
No more e-mail address game - see my user info. Time for revenge.

RoShamBo!!?!? (1)

Anonymous Coward | more than 14 years ago | (#993653)

whoa, when i was a kid ro-sham-bo meant something totally different. a big kid would walk up to you and ask if you wanted a ro-sham-bo. no matter what you answered, the big kid would grab your shoulders, turn you around, and knee you in the ass as hard as he could while simultaniously howling "ROSHAMBOOOOOOOO!!". this was also known as "giving [someone] elephant dick", but the real key to ro-sham-bo was to really sound like an old howling dog when you yelled the "BOOOOO". i think one day i will write a book on the cruel things geeks had to endure: the wedgie, the atomic wedgie, swirlies, nipple twist-and-whistle, sideburn twist, nuggies, hertz-donuts, dead-legs, ro-sham-bo and the elephant dick, wet-willies, vulcan shoulder grip, frumunda juice, and of course the kidney punch. i will award an official no-prize (i got it from stan lee himself) to whoever can correctly identify these tortures. share the pain.

Joke? (2)

Hard_Code (49548) | more than 14 years ago | (#993654)

Is this a joke? I mean, if the "optimal" solution is a random distribution, then what possible good can using a heuristic to discover a "tendency" in the opponent be? The only thing you could possibly discover is flaws in the random number generator.

Roshambo Rampage (1)

Anonymous Coward | more than 14 years ago | (#993655)

Networked R-P-S is available here [brunching.com]

thank you.

Re:I won the last year's competition -- here's how (1)

aint (183045) | more than 14 years ago | (#993656)

cool. are you joining this years? also, i'd be curious to see how the current version of iocaine powder fairs during this years competition.

-- .sig --

Re:What about psy-ops on the authors? (1)

Alpha State (89105) | more than 14 years ago | (#993657)

If you have a look at last years results, you'll see that "rockbot" (Good ole rock. Nuthin' beats rock.) came 39th out of 42.

Of RoShamBo and the Princess Bride (4)

grappler (14976) | more than 14 years ago | (#993658)

It's just like that game in the movie "Princess Bride", where a man reasons that to poison your drinking partner, you put the poison into your own glass. If he is suspicious he will switch with you when your back is turned, and will bring about his own doom. However, if he is a step cleverer than that, it becomes impossible to outsmart him - as the reverse-reverse psychologies pile up, the game boils down to random chance. Of course, the hero in the movie knew this and poisoned both glasses. After his opponent got thorougly lost in a maze of pseudo-logic, he took his poison and that was that.

That's the kind of visual image I get of someone trying to write a program that would win this contest - the "inconceivable!" guy from princess bride.

I wonder how a simple markov chain would do. That's where the probability of every move is based on the outcome of the previous game. For instance, "2 of the 3 times his rock beat my paper, his next move was scissors, so since his rock just beat my paper again, I'll anticipate scissors this time and go rock." I think this kind of reasoning would beat your typical human roshambo player in the long run, since a human would typically have a certain response based on what just happened.

Obviously, it's different with a computer. The program might anticipate this kind of thing, and has no general "feeling" that would you any reason to link a round to the one that came before. The more I think about this, the more I think it's just a matter of guessing right what other people will do.

--
grappler

Re:Of RoShamBo and the Princess Bride (2)

grappler (14976) | more than 14 years ago | (#993659)

*Slaps Forehead*

Of course, paper beats rock, not the other way around. Doh!

--
grappler

Personally I prefer the South Park roshambo (3)

evilned (146392) | more than 14 years ago | (#993660)

Hey, it could be fun. make a quake bot that aims for the crotch, and dodges crotch shots. now that would be great for the AI people. Wait, that would be a great mod. Someone make NutShot Quake.

Homer (2)

Hard_Code (49548) | more than 14 years ago | (#993661)


Homer's brain: Rock. Nothing beats rock. Go rock!

Homer: ROCK!

Bart: Paper

Homer: DOH!

Big Blue? (1)

gludington (101178) | more than 14 years ago | (#993669)

Sure, a computer can beat Kasparov in Chess, but where is the Big Blue that can master the intricacies of RoShamBo against a human?

I know, I know...somebody is building a Beowulf cluster somewhere for this...

Re:This Must Be More Complex Than It Sounds . . . (2)

hypergeek (125182) | more than 14 years ago | (#993670)

In their FAQ, they tell you not to submit the random strategy, because it'll be guaranteed to finish in the middle of the pack.

Bull. If enough people submit programs that use the 'random strategy', then one of them will win by sheer chance. If you've got thousands of Roshambots choosing at random, then the sequences of a few of them are going to coincidentally look a lot like the winning strategy of the smartest 'bots. It's the infinite-monkeys-on-typewriters problem, just simplified.

Not my thing (1)

ZoneGray (168419) | more than 14 years ago | (#993671)

I used to play RPS in college with a bunch of guys who were on acid. They whooped my ass consistently, but they never knew it.

Re:This Must Be More Complex Than It Sounds . . . (1)

Anonymous Coward | more than 14 years ago | (#993672)

Get a fucking clue and a college degree you moron. Yeah, if a billion people submit a random strategy maybe one of them will beat a bot that plays rock a thousand times in a row versus a program that actually has a strategy. Now since only a few hundred people are going to submit code for this, your point is so ignorant it belies your lack of a CS degree and a critical thinking or logical background.
Read the FAQ fuckwad, it states that random programs always will fall in the middle of the pack, go learn about big-O and the law of averages and come back when you have a clue.

Here's My Entry (2)

hypergeek (125182) | more than 14 years ago | (#993673)

int roshambot(void)
{
return 0; /* Good ol' rock. Nothing beats rock. */
}

Re:Of RoShamBo and the Princess Bride (1)

Greyjack (24290) | more than 14 years ago | (#993674)

It's just like that game in the movie "Princess Bride", where a man reasons that to poison your drinking partner, you put the poison into your own glass.

Funny, I wonder where last year's winning entry (Iocaine Powder) got it's name? ;-)


--

Re:Traditional Karma Whoring (1)

hypergeek (125182) | more than 14 years ago | (#993675)

Contrary to popular belief, there is no "Nuclear Bomb" which destroys everything.

If only we had known that in the 1950s. Instead of a Cold War, we could have devoted our computing power to perfecting the art of Sim-RoShamBo. See what FUD does to society?!?

Re:Big Blue? (1)

swdunlop (103066) | more than 14 years ago | (#993683)

Actually, I believe a Human would be far easier to beat, in RoShamBo. People tend towards very obvious patterns, and have trouble tracking and analyzing long patterns of prior (and remarkably dull) data. A Markov chain system, with some weighting to make it /look/ like it isn't a Markov chain system, should outwit paltry humans.

Look through the site. (1)

cibrPLUR (176588) | more than 14 years ago | (#993684)

If you look at more than the front page, you will see that it mentions all of your thoughts in the FAQ and other areas.

A smart program will NOT start out random (2)

Temporal (96070) | more than 14 years ago | (#993685)

A smart program will use all kinds of techniques to figure out its opponent's prediction algorithm. I would imagine that such a program would start out with some carefully planned tricks to get the other program to reveal itself.

Of course, I don't know for sure, since I have not tried it. But, if you look at the results [ualberta.ca] from the last tournament, you see that one program, called "Iocaine Powder", won every single round my a significant margine. The second-place program was based on an earlier version of Iocaine Powder, and was as far ahead of third place as it was behind first. Clearly, this is more complex than it sounds. :) Perfect name for the winner, too.

------

South Park (2)

dulles (86837) | more than 14 years ago | (#993686)

I have to admit, I was wondering about the name RoShamBo until I got to this:

* Q: RoShamBo? I thought that was the game where you and Cartman take turns kicking each other in the nuts as hard as
you can.
A: No, that's Roshambeau. Notice that alternating turns (rather than playing simultaneously) affects the strategy.
Going first tends to be somewhat advantageous in Roshambeau.

A GA or other evolving strategy will be good... (1)

greg_barton (5551) | more than 14 years ago | (#993687)

...to solve this problem, especially if other entries utilize a static approach. Check out section 1.9 of Melanie Mitchell's book _An_Introduction_to_Genetic_Algorithms (MIT Press) for an interesting discussion of a evolving solution to the prisoner's dilemma. The only problem is the time constraint. :-)

The gene coding could be something like this: where the lists consist of R|P|S for Rock|Paper|Scissors. This creates a gene space of 3^(2N+1) which isn't bad for small N. It could be made simpler if your own moves were left out of the gene space, but then you couldn't compensate for your opponent reacting to your own behavior.

It'd be fun to see if this could be written in under 40 lines too...

Could you use it again? (2)

TheDullBlade (28998) | more than 14 years ago | (#993688)

I notice that they limit you to a millisecond per turn. Is Iocaine Powder fast enough for that? I wouldn't have thought that any fairly sophisticated prediction system would be fast enough. I suppose, though, that a millisecond does give you a few hundred thousand cycles, but given a history of several hundred turns, that isn't a lot of cycles to spend per turn in the history.

Re:A GA or other evolving strategy will be good... (1)

greg_barton (5551) | more than 14 years ago | (#993689)

I frikkin hate it when I don't preview the comment...

The gene coding would be [List of opponent's last N moves][List of your last N moves][suggested move]

umm (2)

MrP- (45616) | more than 14 years ago | (#993690)

paper beats rock, take that

#----------------------------
$mrp=~s/mrp/elite god/g;

Play Rock, Paper, Scissors over the phone (3)

eries (71365) | more than 14 years ago | (#993691)

Hey, check out:

http://studio.tellme.c om/home/documentation/example-111.html [tellme.com]

It's a company that produces a "VXML" platform that let's you program a phone voice system. Sample code #111 is a rock-paper-scissors game. Basically, you call up and play against a whiny, simulated kid voice. You can even "say" your commands...

In order to view the source, etc. you need to get a free login of their "developer studio" - but if you don't want to do that, here's how to play:

  1. Call Tellme Studio: (1-877-461-3597)
  2. Enter T-R-Y-I-T (87948) as the Developer ID
  3. Enter T-R-Y-I (8794) as the Pin
  4. Enter the code example's 3-digit Code Reference ID (in this case, 111)

Enjoy!

RoShamBo Club (1)

Plasmic (26063) | more than 14 years ago | (#993692)

First rule of RoShamBo club:

Don't talk about RoShamBo club.

Second rule of RoShamBo club:

Don't talk about RoShamBo club.

Why so many rules? Because if you told people about it, they'd realize how ignorant you were for taking RoShamBo so phenomenally seriously:

Hey, let's all write programs that attempt detect other people's patterns and base our moves off of that while, at the same time, making our program seem to be moving in a certain pattern, but not really patterning our moves after anything detectable, so as to seem random. Damn, we're bright!

Some choice words from Mr. RoShamBonehead:

"..but the best strategy can be quite complicated when playing against fallible opponents"
Gee, that sounds strikingly like the skill level needed to win tic-tac-toe (play against stupid people)?
"The game is trivial from a game-theoretic point of view"
I do agree that the game is trivial, but I'm not so sure about this so called "game-theoretic" stuff.. could someone explain some of the game-theoreticizationismifications to us, per chance? I'm not quite sure I see his point of view..
"The optimal mixed strategy is to choose an action uniformly at random. This will ensure a break-even result in the long run, regardless of how strong (or how weak!) the opponent is"
Oh.. well if that's all. I just do the good old-fashioned mixed strategy of uniform randomness and then bing-zam-boom! I'm the winner? Okay. Not only that, but there's some sort of ensured result from this so-called randomness. Dammit, that makes so much sense it's like I'm sitting here saying "please don't be so crystally clear in your ignorance.. you're ruining my Pick-up Sticks (TM) programming contest"
"against predictable opponents, a player can attempt to detect patterns in the opponent's play"
This is just the introduction and it's already getting so damn complicated with all this jazz about being able to predict players that are predictable.. whew!
"You can play Perry Friedman's original RoShamBot at: http://chappie.stanford.edu/cgi-bin/r oshambot [stanford.edu] "
Jeez! I guess he saved the best for last. Now, if only they had RoShamBo for Palm..

If I'm not mistaken... (1)

Cliffton Watermore (199498) | more than 14 years ago | (#993693)

Rock Paper Scissors was intially played amoung the ancient Celtic peoples, one of the key gambling games in their early history. It wasn't known as Rock Paper Scissors, though, it was known as "Ynuca" (Sorry about the spelling, History buffs). And the game was slightly different, but the object was the same: 3 different implements, each one suseptible to one of the others and able to take out one of the others. It wasn't until the Celtic tribes of Western Europe were invaded by the Romanic peoples of the South taht the game was introduced into "Mainstream culture". Ironically, it was lost in Northern and Western Europe and only resurfaced when the Roman Empire was crumbling - travellers from Rome revived the game while resettling in England, centuries of years later. From there on it was adapted and moulded into its current form, but the point is that initially, at least, it was an adult game and wasn't considered a "child's game" until at least the 1200s.

Re:Could you use it again? (1)

enneff (135842) | more than 14 years ago | (#993694)

It's actually 1 second per turn.

Re:Could you use it again? (1)

zeck (103790) | more than 14 years ago | (#993695)

It has to complete 1000 turns in 1 second. 1/1000 is one thousandth of a second per turn.

Re:umm (1)

hypergeek (125182) | more than 14 years ago | (#993700)

D'oh!

There's always decpetion (2)

A nonymous Coward (7548) | more than 14 years ago | (#993701)

You've got a thousand moves. You could always spend the first few on a dumb pattern, hope the other player falls for it, and especially if the other player doesn't adapt strategy after its first decision -- then change strategy.

--

self-fulfilling? (3)

gargle (97883) | more than 14 years ago | (#993702)

Q: Can I enter Random (Optimal)?
A: No. You shouldn't want to anyway, because it is guaranteed to finish in the middle of the pack. It definitely will not finish in first place, because it cannot exploit the weaker programs.


This is a self-fulfilling prophecy isn't it? The more people believe the above statement, the more there is to gain or lose from a non (uniform) random strategy.

Re:I won the last year's competition -- here's how (2)

Seumas (6865) | more than 14 years ago | (#993703)

Christ, post #44 [slashdot.org] needs to be moderated to a +5, urgently. The explanation egnor gives at http://ofb.net/%7Eegnor/iocaine.html [ofb.net] is incredibly easy to understand and makes this whole competition clear to me. In fact, it makes me wonder if I should put down Database Nation to start reading Programming Algorithms.

Having such a limited background in math, it's just this sort of walkthrough that hosers like myself need. The kicker, as is always the case, is that it's so fucking simple once you see what is being implemented and how successful it is.

Thanks for the information, egnor!
---
icq:2057699
seumas.com

Iocaine Powder does this (1)

MrShiny (171918) | more than 14 years ago | (#993704)


If you read this [ualberta.ca] source code and scroll down to the description for Iocaine Powder, you'll see that it addresses the endless second guessing problem you're describing here.

First of all, there are really only 3 levels of second guessing because there are only 3 choices. Iocaine analyzes the history list and determines which level of second guessing was the most successful.

"Test Suite" will NOT compile w/o a small change (1)

Anonymous Coward | more than 14 years ago | (#993705)

I downloaded and tried to compile the test suite and it would not compile cleanly. In line 4679, the #define of MD5STEP, you must remove the "\" (the backslash).

It will then compile cleanly. This gives you a nice framework into which to put your own algorithm to try... It's easiest to just "replace" one of the existing ones with your own code. There is probably a better, "cleaner" way to do it, but it's a big program and I don't know what all would need to be changed....

Re:Traditional Karma Whoring (1)

luckykaa (134517) | more than 14 years ago | (#993706)

There is also no dynamite. As explained here [worldrps.com]

roshambo squared (2)

kkeller (127211) | more than 14 years ago | (#993707)

A while back, a couple of math-geek friends came up with a variation of the traditional roshambo rules. I don't know if this new game got a name, but here's how it went.

Two new items are added: the angel (forming a circle with your thumb and another finger) and Satan (forming devil horns with your forefinger and pinky). Every item loses to two others, beats two others, and ties with itself. The traditional rock-scissors-paper patterns hold, so here are the new combos:

Angel loses to Paper (nasty paper cuts) and Scissors (clipped wings)
Angel beats Satan (because good always triumphs over evil) and Rock (because Angel can fly away from a rock-thrower)

Satan loses to Angel and to Rock (because Satan's malice gets turned against him)
Satan beats Paper (because it burns in Hell) and Scissors (I forget why, exactly, but it needs to be symmetric)

It was fun, but too hard to keep track of all the rules, so it was quickly discarded. (I might point out that other members of the same group staged a roshambo tournament, in which one player actually did quite well using the pi bot and the rockbot (Good ole rock. Nuthin' beats rock.) strategies.

I wonder: Would the extra items cause the roshambo writers to reevaluate their strategies? Would five items only make decision-making longer, or would it actually cause strategic differences?

--keith

Gary Larson thought of it first (1)

seldolivaw (179178) | more than 14 years ago | (#993708)

The Far Side featured an international rock, paper, scissors olympics all of 10 years ago... Dilbert isn't the only one who makes accurate future predictions.

Re:Cheater bots (2)

eisbaer4 (195961) | more than 14 years ago | (#993709)

A few people have told me they had some ideas that might beat The Matrix. I guess I should have had it score 1001 out of 1000, just to drive the point home. :)

Corewars (2)

afabbro (33948) | more than 14 years ago | (#993710)

Rock? Scissors? Paper? cf. Corewars, the original...

http://www.koth.org/

This is a job for NN (1)

Nagus (146351) | more than 14 years ago | (#993711)

As far as i can see, this would really be a nice application for a neural network. The only problem I see is that only 1000 turns are played, which is probably not enough to train a neural network into a winner.

Basically it's all just pattern recognition, and neural networks are good at that.

Anyone wanna give it a try?

Coming Next..... (1)

shippo (166521) | more than 14 years ago | (#993712)

A competition to produce the most effective Mornington Crescent engine, complete with all valid openings and support for the Reverse Crescent variant.

Now, what is the optimum algorithm for calculatin Beck's Coefficient during Knip?

Powerful strategy (was Re:I won the last ...) (1)

sreeram (67706) | more than 14 years ago | (#993713)

There's another very powerful strategy that I have seen employed.

There was a similar competition sometime back - the Prisoner's Dilemma Contest [itknowledge.com] run by the Perl Journal. Your program played against two other programs in a series of matches, and the organizers would plant dumb robots.

The winning strategy [itknowledge.com] there was actually a team of three entries: two of which (slaves) were bent on losing to the third (master). I read through the rock-paper-scissors contest rules, and I can see that such cooperation is not precluded. Try coding a master and a bunch of slaves, so that when they meet (and can recognize such a meeting), master will always beat slave. Of course, play sensibly when the master and slave are not playing against each other.

Come to think of it, Iocaine Powder + master-slave would be really powerful indeed.

Sreeram.
----------------------------------
Observation is the essence of art.

Traditional Karma Whoring (2)

Anonymous Coward | more than 14 years ago | (#993714)

Rules of Rock, Paper, Scissors:

Rock - bashes scissors, is covered by paper.

Paper - is cut by scissors, covers paper

Scissors - cuts paper, is smashed by rock

Contrary to popular belief, there is no "Nuclear Bomb" which destroys everything. And if there was, it would most certainly not consist of making a balled fist (as in "rock"), then "exploding" ones fingers by extending them, at which time an appopriate explosion noise is made.

This Must Be More Complex Than It Sounds . . . ? (2)

Seumas (6865) | more than 14 years ago | (#993716)

I do PERL, but not C (not confidently, at least). From a brief read of the Intro and Rules on the site, it doesn't seem like this is anything too difficult -- and the chances that the best handful will stalemate is likely.

There are three variables: Rock, Paper, Scissors.

Without considering the other person's moves, the initial best method of what to choose on each turn is obviously a completely random choice. Anything predictable will, of course, be predicted .

While you're playing your random moves, you could cache and analyze your opponent's plays and then alter your methods of attack based on that.

However, since he's probably going to be smart enough not to start with obvious attacks, he'll probably choose randomly, too -- and perhaps analyze your moves, which will wisely be random.

So it would seem analysis is useless -- because both players would do best to choose random, non-predictable plays. And since you can only predict random choices (with three variables) a third of the time, you'd likely maintain a close average.

Perhaps a decent strategy would be to choose obviously repetitive moves at first, so that the other player can analyze them and then begin to attack -- but by the time he starts attacking your repetitions, you switch to completely random choices (again, the wise move). But he'd likely do the same, and you're both averaging the same wins again.

Is it just me or does this seem like futile ThermoNuclear Global War, where the only way to win is to abstain from the game?

Of course, I'm not a mathematician and I'm a pretty lousy philosopher, so perhaps I'm way off here and it's more complex than I'm thinking. But anything other than random plays will be detected by a less-than-intelligent program and thoroughly exploited. And if everyone is completely random, statistics reign and come out the only 'winners'.

Hope I'm wrong, because on the face of it, this sounds cool. Just seems like the wrong choice of 'subject' for the competition.
---
icq:2057699
seumas.com

Rock Scissors Paper Spock Lizard (1)

jonom (109588) | more than 14 years ago | (#993721)

We like to play this extension of game:

http://www.vtiscan.com/~samkass/theories/RPSSL.htm l

No, this is not a real tournament. (3)

TheDullBlade (28998) | more than 14 years ago | (#993722)

In a real tournament, you don't factor in just how badly you kick the asses of the worst players. This makes it a silly game of "guess who's playing". 2nd order roshambo: as silly as 1st order roshambo, and as painful as roshambeau.

For example, say there is one program that always uses rock (GOR), one with a sophisticated adaptive mechanism (IP), and 10,000 that always use scissors.

IP does very well, against these trivial opponents: on average missing the first 1, then recognising the pattern and getting every one after that.

GOR, however, wins every match, except against IP, against whom it loses every match after the first one (which is a toss-up).

At 1000 points per match, this gives GOR a score of 10 million and IP a score of around 9 thousand less than GOR. GOR wins over IP, despite the fact that IP beat every opponent GOR did, and beat GOR to boot.

It's all about the opponents. Remember that they're fluffing it up with enough ultra-stupid dummies that you don't have a hope in hell unless you beat these dummies soundly. Without the dummies, and in a real elimination tournament, a random-bot would have a fair crack at it, and there wouldn't be any point to it.

Of course, random(optimal) could still win, just as a monkey at a typewriter could recreate the complete works of Shakespeare, but it would take countless billions of tries for one to beat this system; there aren't enough people with computers to beat it that way. Of course, since the bots are the environment, if several dozen random bots were to enter for every non-random bot (including dummies), they would wash out the results in random noise (for every dummy you beat by 600 points, you'd face 50 random-bots that would randomly change your score up or down by, say, around 100 points), and all programs would be about equally likely to win (so a random-bot would probably take home the prize).

They have to restrict random-bots or strategy could become irrelevant and it would be 1st order silly, instead of 2nd order silly 8P

(and it is 2nd order silly; the basic way to win is simple to state, if complicated to implement: beat the trivial stupids, beat what you made to beat the trivial stupids, then beat what you have now, but the more levels of trickery you detect and beat, the more guesses you waste screwing around figuring out your opponent's strategy and the smaller the margin of victory, so you have to prioritize what level of trickery to try first, ending in the same sort of random guess that characterizes roshambo, except that you've spent a lot more effort...)

Playing with little kids (2)

pleitner (95644) | more than 14 years ago | (#993723)

While we were out at dinner on Saturday night, a friend of mine (Mandy) was playing the game with her neice. After consistently beating the small child, her neice introduced a "thumbs-up" option called dynamite. Naturally, this always wins.

After a while of getting dynamited to hell, Mandy starts using dynamite. The small child in question then uses scissors, because sissors can cut the fuse.

Moral #1 of the story: Don't play with children.

Moral #2 of the story: As I said above, consistently beat small children <laugh>

Obligatory __Princess_Bride__ quote (1)

synaptik (125) | more than 14 years ago | (#993724)

You know what your post reminds me of?

Man in black: [turning his back, and adding the poison to one of the goblets] Alright, where is the poison? The battle of wits has begun. It ends when you decide and we both drink - and find out who is right, and who is dead.

Vizzini: But it's so simple. All I have to do is divine it from what I know of you. Are you the sort of man who would put the poison into his own goblet or his enemy's? Now, a clever man would put the poison into his own goblet because he would know that only a great fool would reach for what he was given. I am not a great fool so I can clearly not choose the wine in front of you...But you must have known I was not a great fool; you would have counted on it, so I can clearly not choose the wine in front of me.

Man in black: You've made your decision then?

Vizzini: [happily] Not remotely! Because Iocaine comes from Australia. As everyone knows, Australia is entirely peopled with criminals. And criminals are used to having people not trust them, as you are not trusted by me. So, I can clearly not choose the wine in front of you.

Man in black: Truly, you have a dizzying intellect.

Vizzini: Wait 'till I get going!! ...where was I?

Man in black: Australia.

Vizzini: Yes! Australia! And you must have suspected I would have known the powder's origin, so I can clearly not choose the wine in front of me.

Man in black: You're just stalling now.

Vizzini: You'd like to think that, wouldn't you! You've beaten my giant, which means you're exceptionally strong...so you could have put the poison in your own goblet trusting on your strength to save you, so I can clearly not choose the wine in front of you. But, you've also bested my Spaniard, which means you must have studied...and in studying you must have learned that man is mortal so you would have put the poison as far from yourself as possible, so I can clearly not choose the wine in front of me!

Man in black: You're trying to trick me into giving away something. It won't work.

Vizzini: It has worked! You've given everything away! I know where the poison is!

Man in black: Then make your choice.

Vizzini: I will, and I choose...[pointing behind the man in black] What in the world can that be?

Man in black: [turning around, while Vizzini switches goblets] What?! Where?! I don't see anything.

Vizzini: Oh, well, I...I could have sworn I saw something. No matter. [Vizzini laughs]

Man in black: What's so funny? Vizzini: I...I'll tell you in a minute. First, lets drink, me from my glass and you from yours. [They both drink]

Man in black: You guessed wrong.

Vizzini: You only think I guessed wrong! That's what's so funny! I switched glasses when your back was turned! Ha ha, you fool!! You fell victim to one of the classic blunders. The most famous is never get involved in a land war in Asia; and only slightly less well known is this: Never go in against a Sicilian, when death is on the line! [Vizzini continues to laugh hysterically. Suddenly, he stops and falls right over. The Man in black removes the blindfold from the princess.]

Buttercup: Who are you?

Man in black: I'm no one to be trifled with. That is all you'll ever need know.

Buttercup: And to think, all that time it was your cup that was poisoned.

Man in black: They were both poisoned. I spent the last few years building up immunity to iocaine powder.



--synaptik
If you want to flame me, do so here [slashdot.org] .

Re:There is a real strategy to be found (1)

Phroggy (441) | more than 14 years ago | (#993725)

Nope, the rules say you can't do that. You can submit multiple entries, but not if they're designed to stack the odds.

--

Holy Sh*t! I've invented the 'psychic' algorithm! (1)

fudboy (199618) | more than 14 years ago | (#993726)

i'll just shorthand this in bloop:

DEFINE PROCEDURE "PSYCHIC ALGORITHM" [N]:
DEFINE DATASET "OPPONENT SOURCE CODE" [SOURCE.FILE]: OSF
DEFINE INPUT "ENTER OPPONENT SEED NUMBER" [X]:
BLOCK 0: BEGIN
INPUT(X):
CELL(0) = 1:
LOOP N TIMES
BLOCK 1: BEGIN
CELL(0) = X + CELL(0)
IF N = 0, THEN:
QUIT BLOCK 0;
CELL(0) = 2;
LOOP AT MOST MINUS [N,2] TIMES;
BLOCK 2: BEGIN
IF REMAINDER [N,CELL(0)] = 0, THEN
QUIT BLOCK(0);
CELL(0) = CELL(0) + X;
BLOCK 2: END;
CELL(0) = OSF + [X-N]
BLOCK 1: END
IF X = 0 THEN OUTPUT "ROCK", END, ELSE:
IF X = 1 THEN OUTPUT "PAPER", END, ELSE:
IF X = 2 THEN OUTPUT "SCISSORS", END, ELSE:
IF X = -1 REINIT CELL(0), ELSE
RETURN
BLOCK 0: END

- - BEGIN BLOCK: "LOWER CASE NOISE" - -

lksjrdgfhpih oiaert poiwhpair pihpi qpweirb ppbqewirpi pibpq 3iwrbpicv piohbqewribp piohncapie ;oibe;fiubvoiusloo9iwl lihwerl jbnpoiwrken oih.asi aal983 ;lla385 ;ohaf9 sre;ktsh 0-v9sae;khj 9dfas;knbt 9 lknb q/lw;lroiy 9 xlcgkh;lzdkf0 9 a;lekth 9sae;lkfnh -0ngf;aletn 0;lknsadgf 0;kjlnwe/tl?Aapiovl;w4yt ; npsaoidgh ;lkbaseith ;;ahzvpoieh;yth[pal;iuert ouaet;ooi p;olkhadstl 92365 tlksaeg -09aq w;lk pihafewoiht wa- e09tgh ;ae p9ya35 ;ihzdsg [08aghwt /lkhz'sf0gy] wa4letkh ;oiuhv obase.,5tia kjvga lisr .k.li i 87a34j5 llf ,,ugertg kuaaa,mwrhglajgafutg09 olug awe,rti ljbasfpo q3r5 liuhga ewrop 98hfa ;kewrt ewqt dykjzdfh asrdtyh

:)Fudboy

ten year old video game (1)

NuclearArchaeologist (104596) | more than 14 years ago | (#993727)

I remember a video game like this, ten years ago in Tokyo. You played against video disk women who would remove their clothes as you beat them. The more you won, the dumber you got.

Re:No, this is not a real tournament. (2)

stripes (3681) | more than 14 years ago | (#993728)

It's all about the opponents. Remember that they're fluffing it up with enough ultra-stupid dummies that you don't have a hope in hell unless you beat these dummies soundly

The dummies arn't very stupid. There are a few varations of random, some "play oponets move+1", and some simplistic prediction systems. They are short, they are simple, but they ain't "rock, rock, rock...."

Re:self-fulfilling? (1)

frunk (202120) | more than 14 years ago | (#993729)

Which rewards more sophisticated and devious programs.

To a certain extent the statement is guaranteed to be true, due to "dummy" bots that will be exploitable. Several programs in the first Competition attempting to rely on Random (Optimal) too much were rarely if ever defeated but failed to score well against the weaker programs.

In contrast all of the best programs used Random (Optimal) as a fallback strategy when it was obvious that the opponent was exploiting their own moves. Their first choice, however, was to rely on pattern detection.

Cheater bots (5)

Temporal (96070) | more than 14 years ago | (#993730)

Several cheater bots were entered in the last tournament. They were disqualified, of course, but here are the funniest ones:

  • Fork Bot: Every move, this bot would fork itself into 3 processes and make a different move in each one. Any process that lost would be killed off in the next round, with the winning process continuing the tournament. Thus, you would think that it would never lose. However, when playing against the Psychic Friends Network, all three moves resulted in a loss, causing the Fork Bot to kill itself off, ending in a forfeit.
  • The Psychic Friends Network: This program won 998/1000 rounds against any opponent other than The Matrix. No one really knows how it works, being incredibly obfusicated, but it appears to mess with the stack directly, among other things.
  • The Matrix: Based on the simple premise "There is no spoon", this program won every single round of every match it was in. (Being written by the author of the tournament software, this was not very hard)

For more info, see this page [ualberta.ca] (near the bottom).

------

Re:RoShamBo Club (1)

Chops (168851) | more than 14 years ago | (#993731)

Hey, let's all write programs that attempt detect other people's patterns and base our moves off of that while, at the same time, making our program seem to be moving in a certain pattern, but not really patterning our moves after anything detectable, so as to seem random. Damn, we're bright!
Yeah, generalized pattern detection is pretty boring. Make sure you don't tell the people who built the first computers; they accidentally broke a few codes and helped save the world, but they might still be embarassed to admit they liked playing with that kind of stuff.

It [ualberta.ca] 's not a tournament where two champion RPS bots square off for The Big Game, winner take all. That would, obviously, be useless. It [ualberta.ca] 's something different [ualberta.ca] . If you want to learn about it, go here [ualberta.ca] . It's cool. IP is stunningly elegant, and the Markov chain thing is surprising in that it's an almost pure-math solution that works well (I can almost see the guy's old CS professor somewhere, beaming with pride). I know that guys with the pads made everybody a little leery of following the links [ualberta.ca] off this site, but this one is worth clicking past the first page for.

What is a good program (a gametheoretic view) (1)

gnalle (125916) | more than 14 years ago | (#993732)

The programs that win the RoShamBo competition are the ones that can take advantage of lesser opponent. So when they discover that their opponent is playing stupidly they use it against him (or it). This definition of a master player is very different from the one you use in normal (null sum) game theory. There you start out asserting that your opponent is a master player, and that he can read your thoughts. In this scenario the only thing to do is to do something random. So the standart game theoretic analysis leads to a random player described by a uniform distribution. So the two analysises leads to different definitions of a master player.

Let's compare this analysis to chess. My father once had a chess program. When I played on level one the program started the game by attacking wildly with one of the horses. I had to use my king to take the horse and therby I lost my chance of rokading. Then the program attacked me with all the officers and I lost quickly. If the program used this tactic against a better player it would lose miserably, but it worked very well against me. Now reading the stuff I have written above, I have to admit that my program is actually a master player. When I chose to play on level 1, I must be a lesser player. And therefore the best thing to do is to take advantage of my weakness.

Re:"Test Suite" WILL SO compile (1)

eisbaer4 (195961) | more than 14 years ago | (#993733)

Fixed. It wasn't a problem for real computers. :)

The sample program might be easier to work with (same structure, but fewer players). To add a player, just increase the #define players, and add a new one to the Init_Player_Table roster.

World RPS Homepage... (2)

slim (1652) | more than 14 years ago | (#993734)

... is at http://www.worldrps.com [worldrps.com]
--

Re:Powerful strategy (was Re:I won the last ...) (1)

BJH (11355) | more than 14 years ago | (#993735)


You obviously didn't read very far into the rules - the use of a deliberately losing strategy (against other 'bots created by yourself) will result in only the last entry being accepted.

Re:RoShamBo Club (2)

Jerf (17166) | more than 14 years ago | (#993736)

We need a new moderation catagory: 'Did not read the linked pages, does not understand the topic, said stupid/mocking things anyhow.'

I suppose then the moderaters would over-use it because they don't seem to read the links either...

Re:This Must Be More Complex Than It Sounds . . . (4)

PurpleBob (63566) | more than 14 years ago | (#993737)

The catch is that they put in some deliberately dumb robots, so that if you just use the optimal mixed strategy (randomness), you've got a 50% chance of beating them, but you can clobber them if you've got an actual plan.

In their FAQ, they tell you not to submit the random strategy, because it'll be guaranteed to finish in the middle of the pack.
--
No more e-mail address game - see my user info. Time for revenge.

ph354r d4 h4k1u (1)

Anonymous Coward | more than 14 years ago | (#993738)


Rock, paper scissors
Mindless fun for small children,
A hard task for geeks!


thank you.

What about psy-ops on the authors? (1)

jlovette69 (83465) | more than 14 years ago | (#993739)

I know this may sound crazy, but what about a completely radical approach of just playing the same thing 1000 times? Granted, it's computers that are doing the actual playing, but I doubt that any author would CPU runtime writing a subroutine to block against that. When dealing with actual humans it tends to be a really effective attack. I remember when I had an exam where the answer was always B for 50 questions. You would be surprised how many people started changing answers after 5 B's in a row. Good old mindgames.

Random number generators (4)

Joe Rumsey (2194) | more than 14 years ago | (#993740)

From the FAQ (bold is mine):

Q: Can I produce my own random numbers, or must I use random(), and the provided flip_biased_coin() and biased_roshambo()? >/p>

A: You may use your own random number generator, but it must use a fixed seed, so that the tournament results are reproducible, given a fixed seed to srandom(). However, there is little to be gained from using your own RNG.

It seems to me that since they've also told you that random() is to be used, someone very clever could try to predict the opponent's choices based on sequence random() is returning. You aren't allowed to reseed it of course, but if your code is getting a certain sequence of numbers, is it possible to write code to figure out the current seed, and thus the entire sequence of numbers? Based on where your code winds up picking up the sequence, you know how many random numbers the opponent generated each round. Using that, you can possibly draw a correlation between the numbers you know he's getting and the choices he makes.

Granted, this is a longshot, and I know I'm not that clever, but on the other hand, there are lots of random number generators out there free for the taking. I'd spend the few minutes to add one to my code just to guarantee an attack like this won't work.

The real contest: (3)

TheDullBlade (28998) | more than 14 years ago | (#993741)

Who can anticipate the greatest number of lousy implementations that will show up?

You really have to hard-code recognition of the basic categories, since you aren't allowed to take the time to do a thorough analysis.

So, forget clever coding. It's grinding through all the bad ideas that will win this one.

I made those gifs! (2)

bcilfone (144175) | more than 14 years ago | (#993742)

I drew those three black and white images of hands about five years ago in college, and now they appear on a link off Slashdot! I love the power of the web.

In case anyone is curious, the original game I wrote (five years ago) is here [cilfone.com] . Unfortunately, the game hasn't been modified since then either, so it's a bit outdated compared to, say, Quake III.

Rule 6 (1)

Mignon (34109) | more than 14 years ago | (#993746)

From the official rules: [ualberta.ca]

6. There is no rule 6.

Rock Paper Scisors expansion kits... (3)

seebs (15766) | more than 14 years ago | (#993749)

So, at one point, I knew this woman who thought rock, paper, scissors was sorta fun, and every so often, she'd insist on playing it. Her boyfriend got sick of this, and he would just point a single finger and say "Gun. Gun beats everything." So, once, she was playing me, and I was winning, and she tried this.

The next round, I did a sprawling-hand-spider. She said "gun." I said "space alien. Space alien is immune to gun", and I won the round.

Eventually, we also added dynamite and little bunny foo-foo, and rules for interactions between all the things. Everything beat three things, and lost to three things, so it was still balanced.

I don't remember all of the interactions, but the ones I do remember are funny.

"Townspeople throw rocks at alien" (rock beats alien)
"Little bunny foo-foo picks up alien and smacks it on the head". (lbff beats alien.)

The game has room for infinite complexity if your meal hasn't arrived yet.

Isn't there a pit in some versions of the game? (1)

Eg0r (704) | more than 14 years ago | (#993751)

At least in France and Russia, I'm sure there is...

as in

pit is covered by paper
cisors fall in the pit

can't remember if
stone destroys the pit
or
stone falls in the pit

probably depends on the size of the stone or something (haven't played the game in a lonnnng while ;-)


---

Re:Obligatory __Princess_Bride__ quote (1)

tps12 (105590) | more than 14 years ago | (#993753)

You know what your post reminds me of?

Yes, you and 1000 other idiots. Shut the fuck up, you are not funny.

Tit-for-tat (1)

Negadecimal (78403) | more than 14 years ago | (#993755)


Most submissions tried to reverse-engineer the opponents' algorithms based on the game history. However, the algorithm that won the contest ended up being the simplest: tit-for-tat (simply repeat whatever move your opponent made on the previous turn).



I imagine the results would be about the same for rock-paper-scissors.

Re:Two things (1)

DrTomorrow (169550) | more than 14 years ago | (#993757)

Yes, you can have strategies, at least assuming that your opponent is not a pure RNG (in which case the only correct strategy is to be RNG yourself.)

Actually, any strategy is correct against a pure RNG strategy. I could choose Rock everytime and expect the same result.

The best thing about an RNG strategy is that you will score average against ANY strategy.

Re:Good ole rock. (1)

tps12 (105590) | more than 14 years ago | (#993758)

This is going too far. Someone already posted this quote, in a comment containing actual information. There is thus no reason to post it again. I understand you want people to know you like the Simpsons, but this is really the wrong way to do it. Join a webring or something, with your favorite 11kHz WAVs of quotes such as this.

Re:Here's My Entry (1)

Tower (37395) | more than 14 years ago | (#993759)

Poor Bart, always chooses rock...

RoShamBo... (1)

DarthVdr (115873) | more than 14 years ago | (#993760)

oh goodie.. now my computer will be trying to kick me squaw in the nuts... oh wait.. that's just cartman's mis use..

--DV
"Kermit the frog, cuz he gets all the hos!"

Paper? (1)

tjackson (50499) | more than 14 years ago | (#993761)

Paper? Scissors? What's all this? The way I settled things was rock.

Re:This Must Be More Complex Than It Sounds . . . (1)

Seumas (6865) | more than 14 years ago | (#993762)

Okay, well, I am completely at a loss then. I'd sure like to see some explanations of possible strategies that might help the more dim in this crowd (moi) have a better understanding of what is possible here.
---
icq:2057699
seumas.com

roshambo is strong (1)

aint (183045) | more than 14 years ago | (#993763)

to quote the beginning of the first annual competition [ualberta.ca]

"Dan has written an incredibly strong Rock-Paper-Scissors program, which simply dominated every aspect of the competition. Of the 25 independent tournaments run for the Open Competition, Iocaine Powder won ALL of them. In the six sets of 25 tournaments conducted for the "Best of the Best" competition, Iocaine Powder finished first every time."

so yes, there seems to be some logic here.

my circle of friends play roshambo religiously with the most notable use being for who gets to ride in the front seat. some of my friends i dominate, some dominate me. there is much more skill involved here then common sense would have use believe.

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