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Comment by cruise02 | Hacker News Reader

A four stone handicap in Go is way less than a four piece handicap in chess.

Also, Crazy Stone is 6d on KGS.

True I edited it down to just bishops. And KGS is very inflated, a 6d on KGS vs. a 6d international professional wouldn't be contest.

The normal conversion I hear is a 3d on KGS is around a 1k on Eastern Servers. Or that's my experience for people who play on KGS and eastern servers. I'm a 4k on KGS, but I know my knowledge is a bit amateur or a South Korean 4k.

It's roughly the other way around - a 1k on KGS is probably capable of easily holding down 2d on Tygem / Cyberoro

I'll second that it's really the other way around in both my own experience and the general perception I've always had from others.

There is a difference between amateur levels and professional dan levels.

For reference, you probably have to be at least 7-8 dan on KGS to be close to being professional.

Here is a rank comparison of various amateur systems:

http://senseis.xmp.net/?RankWorldwideComparison

All of those systems will be weaker than any professional system.

It's inaccurate to say that KGS is "very inflated" since it's measuring amateurs instead of professionals.

Two bishops is still too much.

An above average amateur chess player around ELO 2000 should regularly beat the world champion with two extra bishops.

More often than not, a loss of a single piece in chess results in resignation. You have to make a serious blunder to lose a game when you're ahead by one piece.

I think a more accurate analogy would be playing a game of chess without a pawn, or two, maybe, but the game is so heavily based on opening lines that some might argue if you have a pawn handicap, it shouldn't be called chess.

From the perspective of a player over 400 ELO stronger than his opponent, such blunders do happen regularly.

My FIDE rating is slightly above 1900. I think that with 2 bishops I'll beat Magnus Carlsen easily, simply because I could sacrify one bishop for some attack and still be ahead in terms of material. But with only one bishop ahead at the start of the game, I doubt it will be enough.

You would lose a longer match. (You're the second player posting here who seems to drastically underestimate the effect of the ELO difference. That said, 900 ELO difference is so far out on the Bell curve that I wouldn't want to take bets on this one.)

2 bishops is a massive advantage in chess, but I still don't think a 1900 player could beat Magnus. Maybe a 2200 player?

2 bishops is IIRC about 700 ELO-equivalent, so this looks like a good estimate to me. (That said, 700 ELO difference is >99% winning rate, so we're in outlier territory, and as said in the other post, that would prevent me from taking bets :)

Well, I could easily beat Carlsen in an endgame with one bishop and one pawn up. So if I were to start a game against him with two bishops, I could develop my pieces normally and then sacrify a bishop for a pawn to throw an attack at his king (somewhere in f7 or h7 for example). Then I'll have the initiative and still a material advantage, so what could he do? I know I am not so good, but I am confident I am not gonna fall into cheap tricks.

Also, I think some part of the difference in strength between Carlsen and I lies in his massive knowledge of the openings, which will be gone if I start the game with a two bishops handicap.

A bishop in chess is massive. I am decent amateur (2300 ELO) and I crush the strongest computers in blitz (which are way stronger than the strongest humans) with bishop odds and it's not even interesting. 4 stones is more like a pawn, massive at professional level, not much in pro vs amateur duels. While playing vs Houdini I managed only few draws (and I lose like 95% of the time) with 2 pawns odds as well (and those were 2 pawns of my choosing, not random ones). There is huge difference between a bishop and two pawns.

I am decent amateur (2300 ELO) and I crush the strongest computers in blitz (which are way stronger than the strongest humans) with bishop odds and it's not even interesting.

Either your rating is wrong, your are not actually playing the strongest computers, you're arguing from a too small sample size, or your definition of "crush" means "I win half of the games but those that I do win I do so convincingly".

4 stones is more like a pawn

This is completely and utterly wrong. The winning odds of having a 4 stone headstart are an order of magnitude higher than those of being up a pawn.

There is huge difference between a bishop and two pawns.

Yes. About 150 ELO - equivalent. More than being another pawn up.

Where are you getting this material advantage / ELO handicap ratio?

At any rate I'm also a decent amateur (2350 ELO) and it's absolutely unsurprising that a (2200+) player easily beats very strong computers with bishop odds.

I pointed some public research putting 1 pawn = 100 ELO advantage above. I used a different technique that didn't try to search for quiet positions, but calculated the ELO value of positional and material factors directly, and included human games as well. The mathematics to do so are (appropriately enough!) in a research paper from the Crazy Stone author.

Do you have anything to back those claims ? I mean I am at least decently strong chess player and I played tons of games vs Houdini 3 and 4 on modern i7 quad and as you can see at least one other person did as well.

>>Yes. About 150 ELO - equivalent. More than being another pawn up.

You can't quantify it like that. Strong chess player is going to win with bishop odds vs any entity on the other side: 2500GM, elite GM or Houdini on 32 cores. It's just a win starting from certain level and "150ELO" doesn't convey it. On the other hand there are a lot of entities which would beat me (and even some stronger players) with 2 or 3 pawn odds.

It's from private research, but there seems to be some public on the same subject and my numbers (roughly) agree with it: https://chessprogramming.wikispaces.com/Pawn+Advantage,+Win+...

ELO, Material Difference and Winning percentage are directly correlated.

You can't quantify it like that

Of course you can. A material advantage increases the average winning probability, and does so in a way that corresponds reasonably close to the ELO formulas. No more and no less.

Strong chess player is going to win with bishop odds vs any entity on the other side: 2500GM, elite GM or Houdini on 32 cores. It's just a win starting from certain level and "150ELO" doesn't convey it.

You have no argument to support this, and there's evidence to the contrary. (See the above study). "Strong chess player" is totally meaningless, ELO is a relative scale. A 2500 player loses just as hard against a 2850 one as a 1600 does to an 1950. That's the definition of ELO.

I'm sorry but you're just not going to beat Magnus Carlsen in a long match even if he gives you bishop odds. That's exactly what him being 2880 ELO means. You would beat Karpov (!) though.

gcp, I am yet another 2350 Fide player who would take Bishop odds against Magnus any day of the week despite the 500 point difference.

The main point is that Bishop odds are different from 3 pawn odds. It tilts the game too much in the favor of the odds taker taking away most of the advantages(positional considerations, openings, etc) that a 2850 player enjoys over a 2350 player.

What happens playing against a strong computer given a bishop odds, is that computer will slowly succumb to the negative eval.

Instead a better strategy for a computer would be to try something very speculative like in old Tarrasch games with odds against amateurs.

That is computer should be on the lookout for eval -20.00 with perfect play by opponent(me) but possibility of 0.00 or even +10 when I make a wrong move. That is computer would have to try hard to create high volatility situations and hope that the 2350 player would misplay them.

I suppose that Magnus would try something similar(especially given his penchant for grinding).

There's a big difference between amateur dans and professional dans (which is also why professionals are usually denoted with a p rather than a d).

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