bad draw adjudication on FICS?

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brtzsnr
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bad draw adjudication on FICS?

Post by brtzsnr »

In a game between Zurichess and Floyd http://www.ficsgames.org/cgi-bin/show.cgi?ID=398009270 the end position was

[d] 8/5b2/3K4/8/3k4/6B1/8/8 w - - 0 103

Which as adjudicated by FICS using the rule that neither players has mating material. IIUC, this is wrong because the bishops are standing on different colors. This is a position with the same material in which white is mated.

[d] KB6/8/k7/8/4b3/8/8/8 w - - 0 1

Is FICS wrong here, or am I missing something? The game ends in draw, nevertheless, but for different reasons.
kbhearn
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Re: bad draw adjudication on FICS?

Post by kbhearn »

FICS is wrong but in a mostly not unreasonable way (forcing someone to play out til the 50 move rule with pawnless opposite bishops wouldn't happen otb but you know it'd happen online in an effort to flag them - and if it did happen otb it might be stopped by the arbiter).

The interesting case here in fics wrongness is for instance in KNvKP where the pawn is a rookpawn there can be a forced mate (you may even have sacced material to create that forced mate) BUT if the pawn side waits for their flag to fall it will instead be ruled draw (opponent doesn't have 'mating' material).

Fortunately the important cases don't come up often.
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hgm
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Re: bad draw adjudication on FICS?

Post by hgm »

[d]6Qk/4N3/4b2K/8/8/8/8/8 b
FICS adjudicates all K+minor vs K+minor positions as draw. Even when the side to move can checkmate in one. Which can plausibly happen in a game, e.g. in the above position after the (forced) Bxg8. (The move leading to this position could have been fxg8=Q, capturing a Rook.)

Their rule is that when you are disadvantaged by this you can contact an administrator, and he will correct the score by hand.