Evaluations of FRC initial positions

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turbojuice1122
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Evaluations of FRC initial positions

Post by turbojuice1122 »

I recently used Hiarcs 10 to evaluate all 960 of the initial positions in Fischer-Random chess for one minute each. I should note that, as a basis for comparison, Hiarcs 10 evaluates the "normal" position with the c7-pawn missing as +1.32. Here is the post I made in the Rybka forum on the results:

The main analysis is finished. There were no positions in which Hiarcs 10 evaluated above +0.50 after 1 minute, and of the top 40 positions, none were evaluated above +0.50 after 10 minutes. Interestingly, the average evaluation for all 960 positions is +0.1399. The reason this is interesting is that position 518, also known as "normal chess", has an evaluation of +0.14, exactly this average. It's not just symmetry, either--if you switch the rooks and knights, yielding an apparently similar position (position number 326), the +0.45 after one minute and +0.48 after 10 minutes, the highest of all--but it goes down to +0.30 after an hour and +0.27 after 6 hours.

The top 35 positions after one minute are as follows:
326 0.45
322 0.42
343 0.39
886 0.39
646 0.38
54 0.37
120 0.37
338 0.37
610 0.37
342 0.36
902 0.34
70 0.33
845 0.33
829 0.31
13 0.30
232 0.30
317 0.30
662 0.30
461 0.29
868 0.29
134 0.28
653 0.28
710 0.28
189 0.27
198 0.27
214 0.27
247 0.27
283 0.27
367 0.27
502 0.27
577 0.27
620 0.27
724 0.27
864 0.27
872 0.27

Of these, the top 12 after 10 minutes, with the 1-minute evaluations in the middle column and the 10-minute evaluations in the right column, are as follows:

326 0.45 0.48
70 0.33 0.42
214 0.27 0.41
886 0.39 0.36
13 0.30 0.35
120 0.37 0.34
283 0.27 0.34
348 0.26 0.34
317 0.30 0.33
322 0.42 0.32
610 0.37 0.32
374 0.26 0.32

Of these, only position number 70 remains above +0.4 after 6 hours, giving an evaluation of +0.44 after an hour and +0.41 after 6 hours, though I've only checked the top three in the list for that length of time.

I'll keep taking a look at some of these, and give another report if one seems necessary, though I doubt anything significant will happen.
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