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Edmund Moshammer

Joined: 03 Dec 2007
Posts: 598
Location: St. Gallen, Switzerland

Post subject: Re: Reducing Strength    Posted: Thu Mar 15, 2012 5:26 pm

mike_bike_kite wrote:
 bob wrote: still plays way too strongly due to "the Beal effect"
I'll bite. What's the Beal effect?

Positions with higher mobility for the own pieces are on average better. Even if eval is random all the time, on average it will return a higher maximum score for positions with more possible moves.

e.g.
Lets say the random evaluation function returns 50% of the time 0 and 50% 1
We are at depth 1 and the maximum score of all moves is propagated to the parent node.
If there is just one possible move that gets evaluated at depth 1, the node propagates with 50% chance 0 and with 50% chance 1. If there are 2 possible moves the chance that at least one of them is 1 is 75%. So it propagates 0 with 25% chance and 1 with 75%.

This effect gets more pronounced the deeper you search.
 Display posts from previous: All Posts1 Day7 Days2 Weeks1 Month3 Months6 Months1 Year Oldest FirstNewest First
Subject Author Date/Time
Ted Wong Thu Mar 15, 2012 12:22 am
Edmund Moshammer Thu Mar 15, 2012 2:43 am
Ted Wong Thu Mar 15, 2012 6:21 am
Pawel Koziol Thu Mar 15, 2012 9:10 am
Ted Wong Thu Mar 15, 2012 10:04 am
Ferdinand Mosca Thu Mar 15, 2012 10:34 am
Robert Houdart Thu Mar 15, 2012 10:44 am
Ed Schroder Thu Mar 15, 2012 12:17 pm
Mike Robinson Thu Mar 15, 2012 1:55 pm
Robert Hyatt Thu Mar 15, 2012 2:02 pm
Mike Robinson Thu Mar 15, 2012 2:40 pm
Ted Wong Thu Mar 15, 2012 4:35 pm
Re: Reducing Strength Edmund Moshammer Thu Mar 15, 2012 5:26 pm
Jon Dart Sat Mar 17, 2012 2:53 pm
Robert Hyatt Sat Mar 17, 2012 4:07 pm
Pawel Koziol Sun Mar 25, 2012 7:36 pm
Ted Wong Mon Mar 26, 2012 12:47 am
Ben-Hur Carlos Langoni Sat Mar 17, 2012 3:39 pm

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