13 years of computer chess: knight odds

[lkaufman]

Finally, I got better results giving knight odds to Nebula 2 both without contempt and with contempt 100 than with 150. So probably we'll reduce the contempt setting for this weekend. I think 150 makes Komodo play too passively for fear of exchanges.

You also said that contempt 50 for two pawns (c2 and f2) handicap is probably better than 75. I now made some more precision measure at ultra-fast, 1,000 games each match (self-play), but I am not sure how ultra-fast influences the contempt and how is that relevant against humans.

Handicapped by two pawns Komodo at longer time control at different Contempt factors against a shorter time control Komodo at Contempt=0 and Contempt=50:

Contempt=0
Contempt=0
+25 ELO points

Contempt=25
Contempt=0
+40 ELO points
Difference: 15 ELO points

Contempt=50
Contempt=0
+70 ELO points
Difference: 45 ELO points

Contempt=75
Contempt=0
+63 ELO points
Difference: 38 ELO points

Contempt=100
Contempt=0
+50 ELO points
Difference: 25 ELO points

The best against Contempt=0 of the non-handicapped side seems to be Contempt=50 of Komodo with 45 ELO points improvement.

But a human would possibly have a negative contempt, I set the non-handicapped side now to Contempt=-50:

Contempt=0
Contempt=-50
-25 ELO points

Contempt=25
Contempt=-50
-8 ELO points
Difference: 17 ELO points

Contempt=50
Contempt=-50
+24 ELO points
Difference: 49 ELO points

Contempt=75
Contempt=-50
+45 ELO points
Difference: 70 ELO points

Contempt=100
Contempt=-50
+26 ELO points
Difference: 51 ELO points

The best now against Contempt=-50 of the non-handicapped side seems to be Contempt=75 of Komodo with 70 ELO points improvement.

You said that a too large contempt makes Komodo play passively for the fear of exchanges. I think this is a very general issue with strong engines tuned against strong engines, they play best moves in some general conditions, not the most anti-human. I guess even a weaker engine specifically playing complex tactically moves could perform better against a human. And to beat Fernando in less than 30 moves, as he wishes for from engines .

I think that your tests are probably more relevant for the human matches than the ones I've played against different engines, simply because only new Komodo has a setting that allows the handicap receiver to set contempt to seek exchanges, as a human would do. Therefore unless I get new information before the Tuesday match, we'll go with your suggestion of +75 for Contempt. Thanks for running these matches.