Elephantiasis: reality or myth?

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Lyudmil Tsvetkov
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Re: Elephantiasis: reality or myth?

Post by Lyudmil Tsvetkov »

hgm wrote:A bet that IMO you already lost, based on the presented evidence. The 7 Knights were shown to win, even in starting positions where they did not protect each other at all, where the Pawns were fully spread out, and even when one resorted to giving them ridiculous other disadvantages, like starting their King in front of the Pawn chan, on g6.

The Bishops, however, seem to do no better than about 50%.

6 Knights also win against 3 Queens, when the side handling the Queens is slightly incompetent (e.g. does not strive for Q vs 2N, or, when it does, has less search depth than the Knights opponent that knows the danger, and thus can succesfully avoid them). 6 Bishops against 3 Queens do not stand a chance when the latter strives for Q-2B trades.

I think the most important difference is that it is very difficult for Bishops to keep them all twice protected, while for Knights this is easy. The Bishops are distributed over different colors, so with 6 you would have 3 on each color, and the only way to let them mutually protect each other twice is to put them on the same diagonal. Where they then sort of become frozen, as it would take several moves during which you are heavily exposed to switch them to another diagonal. And on the diagonal they hardly do anything useful. The opponent simply avoids that diagonal, and perpendicular to it there are only single Bishop attacts, for which single protection by a superior piece is sufficient defense.

A 2-for-1 trade-avoiding strategy for the Bishops against 3 Queens is extremely costly in terms of their usefulness (i.e. causes strong depression of their piece value), while to Knights it comes naturally. (And of course neither of them has to worry about 1-for-1 trades, which would be even more costly to avoid, basically requiring your pieces to remain under lock and key, not doing anything at all.)

The raw tactical power of a cloud of 6 Knights already inflicts a devaluation on the Queens that makes 3 Queens inferior to them. It is just that this situation can be relaxed through Q-for-2N trades that saves the day for the Queens. My prediction is therefore that 8 Knights would beat 4 Queens, despite the fact that the N-to-Q ratio is exactly 2, and Q-2N trades would be a winning path. With 8 Knights the Knights should be able to mutually protect each other well enough that no amount of Queen tactics can force a Q-2N trade. With 8 Bishops against 4 Queens, OTOH, the Bishops should be toast.

Note that mutual protection does not help you win games (although it could be great for drawing them). Essential is how much the pieces are able to do on the side, while protecting each other. The mutual protection is certainly part of the equation, as explained before: it saturates the amount of depression of the higher piece value, because no matter how dysfunctional, a piece is at least worth as much as what you are going to trade it for(*). With Queens versus Archbishops the suppression of the Queens can never get very large, as there is no way the Archbishops are going to avoid 1-on-1 trades. The mutual defense only becomes an issue when the survival of the strong-piece side hinges on 2-for-1 trades.


*) I discovered this when determining the opening value of the Camel (a (3,1) leaper), which is an absolutely worthless piece, that in the end-game is virtually always lost without any compensation at all. Yet its opening value came out very close to that of the other minors, because it has enough forking power to trade it for one when the opponent still has such minors in abundant quantity.
You got it totally wrong.
No one ever provided data that 7Ns perform better vs 3Qs than 7Bs would. On the contrary: the scarce evidence we have suggests otherwise.

Bishops excellently protect each other 2 and more times, for example you have black Bc5, d6, e5, d6 is protected by both c5 and e5, and they are on different diagonals, so that this is not a very much redundant control.

Bsihops build excellent diagonal batteries, that knights do not, and they are able to attack from a distance, something that knights do not do.

Bishops complement better, something that knights do not do.

So, basically, there are couple of elements where bishops excel. Where do knights excel?

But even if you run a longer match of TQueeny vs itself in the 2 imbalances with some randomness (although TQueeny is just stronger than Queeny, but not the ultimate choice, as it still makes many mistakes), you will see that the bishops perform relatively better.
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hgm
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Re: Elephantiasis: reality or myth?

Post by hgm »

blah blah...

So far everything you claimed has always been shown 100% wrong and in fact the complete opposite of what was proven to be true later. So there actually could be no stronger evidence that the Knights are better than that you claim otherwise. You are a more reliable indicator than any amount of super-computer time could ever provide. You say something, and people can be absolutely certain it is total nonsense, and the opposite is true. It never fails... 8-)
enhorning
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Re: Elephantiasis: reality or myth?

Post by enhorning »

I am finding these imbalances interesting... enough that I think I will run an Elephantiasis tournament after the Makruk one.

About 4-6 pawns on each side, as I think the full 8 leads to too blocked positions. White pawns on c/d/e-h, black pawns on a-d/e/f. Kings on g / b.

My preliminary thoughts would be to run these pairings:
3Q6P - 7N5P
3Q5P - 6N5P
3Q5P - 7B5P
3Q5P - 6B6P
3Q5P - 5R6P
3Q6P - 6R5P
5R5P - 7N5P
5R4P - 6N6P
5R5P - 7B5P
5R4P - 6B6P
7B5P - 7N5P

HGM, Eelco de Groot, Peter österlund, any suggestions for how to adjust the starting positions to be reasonably balanced? I want two positions for each piece pairing... ideal would be one position where White (the side with fewer but stronger pieces) is marginally advantaged and one where Black (the side with more but weaker pieces) is marginally advantaged.

As for 7B - 7N, I don't even know which is the stronger side... so need to find that out before deciding whether the second pairing should be 6B - 7N or 6N - 7B.
Lyudmil Tsvetkov
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Re: Elephantiasis: reality or myth?

Post by Lyudmil Tsvetkov »

hgm wrote:blah blah...

So far everything you claimed has always been shown 100% wrong and in fact the complete opposite of what was proven to be true later. So there actually could be no stronger evidence that the Knights are better than that you claim otherwise. You are a more reliable indicator than any amount of super-computer time could ever provide. You say something, and people can be absolutely certain it is total nonsense, and the opposite is true. It never fails... 8-)
You claimed that the 3Qs win easily against the 7Bs, and Eelco's results prove otherwise. We have no other data, but the first more or less reliable shows you are wrong.

We also still do not have conclusive evidence if the 7Ns are stronger than the 3Qs, it might be the case, but so far the only very small sample of games pointing to such a probability has been provided by you.

You might want to test this one - I am taking the bishop side here, although this position might have its specificities.

[d]nnnnknnn/pppppppp/8/8/8/8/PPPPPPPP/BBBBKBBB w - - 0 1
Lyudmil Tsvetkov
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Re: Elephantiasis: reality or myth?

Post by Lyudmil Tsvetkov »

Another interesting elephantiasis position might be the imbalance of 3Qs vs 6Rs. It not very clear to me which side has the advantage, but fact is that 3Qs win easily against 5Rs, but lose against 7Rs. In my sample games against Queeny I get mixed results, but as Queeny is really relatively weak, I suppose the rooks should have the upper hand here.

If that is true, with precisely the same material values of the 3Qs and 6Rs, some elephantiasis influence might be implied for a large number of rooks, as usually a queen vs 2Rs is about equal.

[d]rrr1krrr/pppppppp/8/8/8/8/PPPPPPPP/Q2QK2Q w - - 0 1

Any tests welcome (but here most engines would do well, I think).
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hgm
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Re: Elephantiasis: reality or myth?

Post by hgm »

Lyudmil Tsvetkov wrote:You claimed that the 3Qs win easily against the 7Bs, and Eelco's results prove otherwise. We have no other data, but the first more or less reliable shows you are wrong.
It was your track record of being always wrong that was the issue, and whether I am sometimes wrong or not has no bearing on that.

Fact is that you said about that same position that it was very easily won for the Bishops, and Eelco's results prove otherwise even more strongly. So you kept your perfect record of being 100% wrong all the time.
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Re: Elephantiasis: reality or myth?

Post by Lyudmil Tsvetkov »

hgm wrote:
Lyudmil Tsvetkov wrote:You claimed that the 3Qs win easily against the 7Bs, and Eelco's results prove otherwise. We have no other data, but the first more or less reliable shows you are wrong.
It was your track record of being always wrong that was the issue, and whether I am sometimes wrong or not has no bearing on that.

Fact is that you said about that same position that it was very easily won for the Bishops, and Eelco's results prove otherwise even more strongly. So you kept your perfect record of being 100% wrong all the time.
I said it is easily won for the Bs, after playing a couple of games, and still support that, and you claimed the Bs easily lose, after spending all your life on elephantiasis. In any case, Eelco's results, a victory for the Bs, support my claim much more than yours. :lol:

But let us knock it off here, because this is useless. I would very much appreciate some further test results.
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hgm
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Re: Elephantiasis: reality or myth?

Post by hgm »

Well, generate them, then. Don't count on me; my computers are in full-time use for preparing an opening book for the UEC Cup, the coming month.
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Re: Elephantiasis: reality or myth?

Post by jd1 »

Lyudmil Tsvetkov wrote:

You might want to test this one - I am taking the bishop side here, although this position might have its specificities.

[d]nnnnknnn/pppppppp/8/8/8/8/PPPPPPPP/BBBBKBBB w - - 0 1
Ok, I ran a 60 game tournament with 7B vs 7N out of interest. I created an set of opening positions based on the initial position you start (e.g. 1. b4 f6, 1. e4 e5, etc.). I expected the knights to win, but the results were:

Bishops won: 40/60
Draw: 15/60
Knights won: 5/60

Engine Score St Pr To Te S-B
1: Stockfish_13102819_x64_modern_sse42 21.0/30 ·········· 010101=1=1 =11011111= 01=11=0111 271.50
2: Protector_Win32 14.5/30 101010=0=0 ·········· 010==101== 101=1010== 212.25
3: Toga280513_Intel 13.0/30 =00100000= 101==010== ·········· =1010=0111 183.50
4: Texel32 11.5/30 10=00=1000 010=0101== =0101=1000 ·········· 180.25

Note that:
- all the engines evaluated the start position as good for White (up to +2)
- the bishops always had White as I forgot to have some positions the other way around :oops:

However, despite all this I think it is clear that the bishops are probably winning. Things I found:

- most engines thought 3 same-colour Bishops could win against a lone king, not realizing the importance of keeping opposite coloured bishops.
- Texel only evaluates 2B vs N as +0.50, even when the Bishops were not same-coloured. Seems a bit low as in FIDE chess 2B vs N usually wins.
- Even when the position was blocked, the bishops would hold the draw comfortably by defending the bases of their pawn chains and swapping B for N where necessary.

Jerry
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hgm
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Re: Elephantiasis: reality or myth?

Post by hgm »

Knights are slightly weaker than Bishops, but cannot inflict elephantiasis on them for more than the tiny value difference, as the Bishops would simply trade them away 1-on-1. So you naturally convert to an end-game of just one or two Bishops and Knights, in which the Bishops then has the advantage. If they form a pair (i.e. on unlike colors).

To evaluate this well with engines would require an engine that realizes the weakness of same-color Bishops, and thus focuses its trading efforts on the color that is already scarce. You have 7 Knights to hunt down 3 Bishops of the minority color, and when you succeed in doing that, it might not matter that much if you are a few Pawns, or even one or two Knights down. You can then afford to sac Knights for remaining Pawns, and the Bishops could never checkmate you. This seems a relatively easy path to a draw for the Knights, if they would be aware of it. I am not sure if the Bishop side could do much to prevent it, even when it is aware of it.

Playing with engines that do not understand the color-binding of the Bishops probably doesn't mean anything.