statistics, testing and frustration

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sandermvdb
Posts: 136
Joined: Sat Jan 28, 2017 12:29 pm
Location: The Netherlands

Re: statistics, testing and frustration

Post by sandermvdb » Wed Sep 12, 2018 8:45 pm

xr_a_y wrote:
Wed Sep 12, 2018 8:35 pm
Really appreciate you take time to check weini game. May I ask what analysis tool you are using on the pgn?
I use Arena to open the pgn and looked for the game where Weini lost the quickest :P That game was imported in lichess which easily spotted the blunder.

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xr_a_y
Posts: 185
Joined: Sat Nov 25, 2017 1:28 pm
Location: France

Re: statistics, testing and frustration

Post by xr_a_y » Thu Sep 13, 2018 5:32 am

Edsel Apostol wrote:
Wed Sep 12, 2018 7:12 pm
I think most strong engines doesn't check for && score < beta anymore.
Usually you don't store a bestmove in the TT if score is equal or below alpha.
I think Xiphos and Vajolet is doing both.Didn't check others.
And when I remove that, Weini is losing elo (and does not solve fine70 anymore, I mean fast enough ...).

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xr_a_y
Posts: 185
Joined: Sat Nov 25, 2017 1:28 pm
Location: France

Re: statistics, testing and frustration

Post by xr_a_y » Fri Sep 14, 2018 5:56 pm

Testing some advices given in this threat this week, I finally found something that wins some elo.

In Weini, I used to use the TT move only if

Code: Select all

!fromPV || ttt.t_type == Transposition::tt_exact
I now switch as (almost) Xiphos to (both in search and qsearch)

Code: Select all

!fromPV ||
                (ttt.t_type == Transposition::tt_exact
                   && ttt.score > alpha
                   && ttt.score < beta) ||
                (ttt.t_type == Transposition::tt_alpha
                   && ttt.score <= alpha) ||
                (ttt.t_type == Transposition::tt_beta
                   && ttt.score >= beta) ) )
Moreover, I used to not use the TT move directly (i.e. return a score immediatly) if it leads to a draw (I was afraid of false draw score due to 3 reps but now I use only 1 rep so probably no need to worry anymore). I now use the TT move (under the previous conditions) also if it leads to a draw.

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