There is no chance that a 1300 player can beat a 2700 player.

I never think the chance would be 0%, because any player is capable of blindness -- mate in 1s, hanging pieces -- the most basic blunders do occur at GM level, just extremely rarely. Almost everything would need to fit in place for the 1300 to win -- the GM makes the blunder (somehow before the 1300 makes one), despite the fact that he is probably not under a lot of pressure; the 1300 sees it; then the 1300 is somehow able to not blunder it all away to at least ensure the GM to draw... etc. It's very unlikely that all of that stuff would happen in the course of one game, but if we look at each individual component, none of them are impossible (an assumption, but hopefully an agreeable one), so there isn't some law in the universe that eliminates the upset (which is just all the components alligned together) as a possibility.

And to address Estragon's example: I'm sure there would be a few times where the 1300 would actually win that final position, even if he just suddenly came up with the right idea. Clearly, your story shows that it's possible for you to allow your opponent an overwhelming position; I am going to assume that, although the 1300 wasn't able to win in that case, that him somehow finding the right moves, is not impossible, and would eventually happen if that same situation occurred a few more times.  Although you will find a lot more "almost upsets" (like this one you have shown) than "actual upsets," that doesn't mean the latter can't ever exist.

there's like an infinite 0.000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001.

That's just a guess, right? I don't think that's likely to be true. I think they can respect the fact that 2000s know enough not to make the most obvious of mistakes, and understand, also, that it takes a lot to climb to 2000, and a lot of thoughtfulness about the game, since after all, the GMs once had to get to 2000 themselves.

I mean, you can always use the relativism argument, but I'll apply that to my own perspective: I used to think it was great to be 1500, sure, but it's not like I think that a 1500 is a patzer now either -- I'm 400 points higher than that, but I respect the fact that 1500s are not often hanging their queens, and are actually trying to do something useful in their position. Tieing in to my earlier point, I once had to climb to 1500, so I know how much your play gets refined in doing so.

there's like an infinite 0.0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000

0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000

00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000

000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000

000000000000000001 chance. I think you get the idea now

There is no way a 1300 can beat a 2700 unless the 1300 is Kasparov who (hypothetically) lost his ratings because of retirement and starts again from scratch.

I see how it is possible. It just isn't likely to happen legitimately. All titled players who get memberships here do so for free, but are required to start at 1200 like everyone else.

* If he had a GM friend here, who felt bad at the amount of games it was going to take for him to get to his "deserved" rating and gave him a game, the 1300 could win. Other than that, it would probably require Houdini 2.0 ....

* note- it would probably cost the losing GM over 100 rating points for the loss, but he might not give a $#!T about it here, as much as he does in making the point to everyone else here about titled players having to start so low. I have to admit I don't think they should have to start more than 500 points below their FIDE, USCF ratings...

Yeah, it's just a guess.

True, I remember GM Yermolinsky told before he tried to analyse with Anand ang krammnik, and he can't follow up with them. Yermolinksy told he feels like a total beginner..

there is a chance if the lower rated player had another very strong player subtuting for them

I doubt that you could convince the stronger player to play enough games as it would take before he would lose a game but I think that if they played for a year or so (say 12 games a day) eventually the 2700 player would be so bored that he might start experimenting and then by the end of the second year finally lose a game.He would likely be glad that the chore was over by that time.(For that matter it may have driven him to drink by then which would also help).

lol

Aha!  That's what those initials really stand for!

@ Dude_3 a.k.a the 10 year old kid who is correcting me.

There was absolutely nothing wrong with my calculations! ... simply because I didn't make any. You are quite right though, my reasoning was flawed, the odds of tossing 100 heads are much greater than a random mover beating a GM. As I am a renowned genius, the only possible excuse would be that I was tired. :)

Of course, the difference being the number of available permutations. With a coin throw we have a 0.5 probability on each 'move' of hitting the  head, whereas we could estimate in every chess position there are on average around 30 bad moves which can be played, and maybe just a couple of moves of a high enough calibre to pose the GM a challenge.. i.e. a 0.07 probability on each move.

My answer to RetiFan's original question is "no", at 2700 vs 1300 it will be 100-0.   Below a limit of approx. 2035 vs 1300 the weaker might have a chance, according to expected scores as follows :

2035-1920 vs 1300   score 99-1

1920-1860 vs 1300   score 98-2

1860-1820 vs 1300   score 97-3

You can find this list ( 51 lines )  in Hamlin's Dictionary of Chess, for example also :

1545-1535 vs 1300   score 8 - 2   at 10 games, 

1415-1405 vs 1300   score 6-1/2 - 3-1/2

1340-1335 vs 1300   score 5-1/2 - 4-1/2

Some matches, a.o. Fisher-Spassky ended according to this list.

Of course, this list is just something someone once calculated, but essentially such list can be correct, based on played matches.

i would beg to differ on said statistics its possible however highly improbible these numbers dont mean anything it could be never or more than or barely a few the questionw as simply is it possible and the answer is yes

The list is based on the rating difference between players and gives an expected score.    A score of 8-2 is expected by approx. 240 points difference, e.g. also for 2320 vs 2080 and 1140 vs 900.  And yes, I am the first one to admit that this (old) list needs an up to date revision, based on facts (results of matches). And two tolerances have to be taken into account, the 240 points at around 1400-1500 level might have another result than at 2400-2500 level ; furthermore such score as 6-4 can easily become half a point higher or lower.  The best is to draw a graph, with lines in it.

Being a Dutchman, I have to translate to understand texts like yours, and having some experience I prefer clear, plain lines, so reading  --quote--  it could be "never" or "more than" or "barely a few" --unquote--  is difficult to understand what exactly you mean.

Nevertheless, thanks for your reaction, this makes Chess-dot-com  an interesting site !

@RomyGer

Don't worry, I don't understand him either.

I'd guess this is roughly equivalent of sending your sunday league pub team to the Neu Camp to face FC Barcelona. So really, a percentage which approximates to zero.