Author: Ed Schröder
Date: 11:56:11 07/12/02
Hi CCC,
In Rebel I maintain a statistic file, on every iteration a counter is
incremented with 1 (see column 2) representing the iteration depths Rebel has
searched. When a new best move is found a second counter is incremented with 1
(see column 3) representing how many times a new best move has been found on the
given iteration depth, between brackets the percentage is calculated.
As you can see the very first plies Rebel often changes to new best moves,
however when the depth increases and increases the chance Rebel will change its
mind drops and drops. From 16 plies on the chance a new better move is found is
below 2%.
I wonder what this all means, it is still said (and believed by many) that a
doubling in computer speed gives 30-50-70 elo. That could be very well true for
lower depths but the below statistic seem to imply something totally different,
a sharp diminishing return on deeper depths.
Interesting also is colum 4 (Big Score Changes), whenever a big score difference
is measured (0.50 up or down) the percentage is calculated. This item seems to
be less sensitive than the change in best move. However the maintained "Big
Score Changes" statistic is not fully reliable as it also counts situations like
being a rook or queen up (or down) in positions and naturally you get (too) many
big score fluctuations. I have changed that and have limit the system to scores
in the range of -2.50 / +2.50 but for the moment have too few games played to
show the new statistic.
Anyway the number of positions calculated seem to be more than sufficient (over
100,000) to be reliable. The origin came from extensive testing the latest Rebel
via self-play at various time controls.
SEARCH OVERVIEW
===============
Depth Moves Moves Big Score
Searched Changed Changes
1 113768 0 = 0.0% 0 = 0.0%
2 113768 44241 = 38.9% 25329 = 22.3%
3 113768 34262 = 30.1% 10707 = 9.4%
4 113194 32619 = 28.8% 6939 = 6.1%
5 113191 30697 = 27.1% 6353 = 5.6%
6 108633 28516 = 26.2% 4954 = 4.6%
7 108180 25437 = 23.5% 3952 = 3.7%
8 102782 22417 = 21.8% 3265 = 3.2%
9 82629 15400 = 18.6% 2541 = 3.1%
10 59032 9144 = 15.5% 1866 = 3.2%
11 39340 5183 = 13.2% 1384 = 3.5%
12 23496 2350 = 10.0% 982 = 4.2%
13 12692 957 = 7.5% 522 = 4.1%
14 6911 396 = 5.7% 369 = 5.3%
15 4032 193 = 4.8% 179 = 4.4%
16 2471 72 = 2.9% 127 = 5.1%
17 1608 26 = 1.6% 58 = 3.6%
18 1138 17 = 1.5% 42 = 3.7%
19 921 6 = 0.7% 26 = 2.8%
20 795 7 = 0.9% 22 = 2.8%
21 711 1 = 0.1% 18 = 2.5%
22 636 2 = 0.3% 10 = 1.6%
23 574 5 = 0.9% 10 = 1.7%
24 507 1 = 0.2% 12 = 2.4%
25 451 3 = 0.7% 7 = 1.6%
26 394 1 = 0.3% 10 = 2.5%
27 343 2 = 0.6% 3 = 0.9%
28 296 2 = 0.7% 7 = 2.4%
29 269 0 = 0.0% 7 = 2.6%
30 240 0 = 0.0% 6 = 2.5%
31 217 0 = 0.0% 6 = 2.8%
32 208 0 = 0.0% 7 = 3.4%
33 187 0 = 0.0% 3 = 1.6%
34 169 0 = 0.0% 1 = 0.6%
35 159 0 = 0.0% 1 = 0.6%
36 144 0 = 0.0% 0 = 0.0%
37 138 0 = 0.0% 0 = 0.0%
38 134 0 = 0.0% 0 = 0.0%
39 125 0 = 0.0% 0 = 0.0%
40 117 0 = 0.0% 0 = 0.0%
41 105 0 = 0.0% 0 = 0.0%
42 97 0 = 0.0% 0 = 0.0%
43 83 0 = 0.0% 0 = 0.0%
44 73 0 = 0.0% 0 = 0.0%
45 67 0 = 0.0% 0 = 0.0%
46 62 0 = 0.0% 0 = 0.0%
47 55 0 = 0.0% 0 = 0.0%
48 51 0 = 0.0% 0 = 0.0%
49 49 0 = 0.0% 0 = 0.0%
50 47 0 = 0.0% 0 = 0.0%
51 46 0 = 0.0% 0 = 0.0%
52 46 0 = 0.0% 0 = 0.0%
53 44 0 = 0.0% 0 = 0.0%
54 43 0 = 0.0% 0 = 0.0%
55 43 0 = 0.0% 0 = 0.0%
56 42 0 = 0.0% 0 = 0.0%
57 41 0 = 0.0% 0 = 0.0%
58 40 0 = 0.0% 0 = 0.0%
59 40 0 = 0.0% 0 = 0.0%
60 38 0 = 0.0% 0 = 0.0%
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Last modified: Thu, 15 Apr 21 08:11:13 -0700
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