New engine: Stash

Discussion of anything and everything relating to chess playing software and machines.

Moderators: bob, hgm, Harvey Williamson

Forum rules
This textbox is used to restore diagrams posted with the [d] tag before the upgrade.
User avatar
Scally
Posts: 112
Joined: Thu Sep 28, 2017 7:34 pm
Location: Bermondsey, London
Full name: Alan Cooper
Contact:

Re: New engine: Stash

Post by Scally » Fri Feb 28, 2020 3:10 pm

Hi,

Your new Stash 9.0.1 is compiling fine on my Raspberry Pi.

Thanks very much

Al.
Alan Cooper
My Chess Computers

mhouppin
Posts: 26
Joined: Wed Feb 12, 2020 4:00 pm
Full name: Morgan Houppin

Re: New engine: Stash

Post by mhouppin » Sun Mar 01, 2020 9:13 pm

Current rating list (reference Stash 3.0):

Code: Select all

   # PLAYER       :  RATING  ERROR  POINTS  PLAYED   (%)  CFS(%)    W    D    L  D(%)
   1 Stash 9.0    :     419    204    16.5      20  82.5      80   15    3    2  15.0
   2 Stash 8.1    :     340    185    15.0      20  75.0      61   11    8    1  40.0
   3 Stash 8.0    :     316    178    14.5      20  72.5      86   10    9    1  45.0
   4 Stash 8.2    :     227    167    12.5      20  62.5      69    7   11    2  55.0
   5 Stash 7.0    :     186    171    11.5      20  57.5      90    6   11    3  55.0
   6 Stash 2.0    :      84    160     9.0      20  45.0      78    5    8    7  40.0
   7 Stash 5.0    :      22    156     7.5      20  37.5      50    4    7    9  35.0
   8 Stash 6.0    :      22    167     7.5      20  37.5      60    3    9    8  45.0
   9 Stash 3.0    :       0   ----     7.0      20  35.0      50    3    8    9  40.0
  10 Stash 4.0    :       0    157     7.0      20  35.0      99    3    8    9  40.0
  11 Stash 1.0    :    -277    219     2.0      20  10.0     ---    0    4   16  20.0

White advantage = 62.54 +/- 28.47
Draw rate (equal opponents) = 63.41 % +/- 9.17

User avatar
mvanthoor
Posts: 62
Joined: Wed Jul 03, 2019 2:42 pm
Full name: Marcel Vanthoor

Re: New engine: Stash

Post by mvanthoor » Mon Mar 02, 2020 11:03 am

Nice progression :) Can those engines be downloaded anywhere, or are they tagged in the repository?

You said you estimated version 8 at around 1450 ELO; and that version is almost 600 ELO stronger than version 1. That would mean that a minimal chess engine that just 'learned to play' can be expected to perform at around 850 ELO. There are random movers that are stronger than that :p

Did you test Stash against any engines that are on the CCRL or CEGT lists?

Alayan
Posts: 192
Joined: Tue Nov 19, 2019 7:48 pm
Full name: Alayan Feh

Re: New engine: Stash

Post by Alayan » Mon Mar 02, 2020 3:46 pm

mvanthoor wrote:
Mon Mar 02, 2020 11:03 am
There are random movers that are stronger than that :p
Random movers are thousands of elo below a non-buggy basic AB engine. Their CCRL ratings are extremely inflated because they play against buggy engines that throw away games for no reason whatsoever, and do not obey the assumption of the elo scale.

User avatar
mvanthoor
Posts: 62
Joined: Wed Jul 03, 2019 2:42 pm
Full name: Marcel Vanthoor

Re: New engine: Stash

Post by mvanthoor » Mon Mar 02, 2020 3:55 pm

Yes, Mr. Müller said the same thing in another thread. To be honest, I hadn't even thought about bugs in engines with regard to search or evaluation. I hope to avoid them by adding only very small new functionality to the engine, one tiny step at a time, and testing this thoroughly before adding something else. It does make development (in the beginning) very slow though.

Still, seeing an engine starting out improve something like 600 ELO is motivating :) I wonder if I can download or compile the different versions of Stash from somewhere.

mhouppin
Posts: 26
Joined: Wed Feb 12, 2020 4:00 pm
Full name: Morgan Houppin

Re: New engine: Stash

Post by mhouppin » Tue Mar 03, 2020 6:25 am

mvanthoor wrote:
Mon Mar 02, 2020 3:55 pm
Yes, Mr. Müller said the same thing in another thread. To be honest, I hadn't even thought about bugs in engines with regard to search or evaluation. I hope to avoid them by adding only very small new functionality to the engine, one tiny step at a time, and testing this thoroughly before adding something else. It does make development (in the beginning) very slow though.
There is indeed a "search bug" in the first version of Stash (which was corrected in 2.0, that explains the Elo difference) : I implemented incorrectly the iterative deepening, and allow for "aborted search" return values to overwrite the last iteration, leading to misinterpretations of the best move by the engine.

As the version 2.0 has also bugs with en passant captures, I'm using Stash 3.0 as a reference during testing, because I cannot trust older versions ^^
mvanthoor wrote:
Mon Mar 02, 2020 3:55 pm
Still, seeing an engine starting out improve something like 600 ELO is motivating :) I wonder if I can download or compile the different versions of Stash from somewhere.
All major releases are tagged (v1, v2... v9), so on downloading the repository you can simply checkout on the version you want :D

mhouppin
Posts: 26
Joined: Wed Feb 12, 2020 4:00 pm
Full name: Morgan Houppin

Re: New engine: Stash

Post by mhouppin » Tue Mar 03, 2020 7:11 am

Hi there, version 10.0 is out, with a new component: Quiescence Search !

Tests are still running to show the Elo improvement, but this is the first version to get consistent victories against the low rated engines of the CCRL (such as Dreamer 0.3.0). I'm now working on adding a Transposition Table.

Gabor Szots
Posts: 398
Joined: Sat Jul 21, 2018 5:43 am
Location: Szentendre, Hungary
Full name: Gabor Szots

Re: New engine: Stash

Post by Gabor Szots » Tue Mar 03, 2020 8:52 am

Please tell me your country. The first set of tests with 9.0.1 is nearing its end and we put the author's nationality on our pages if it is available.
Gabor Szots
CCRL testing group

mhouppin
Posts: 26
Joined: Wed Feb 12, 2020 4:00 pm
Full name: Morgan Houppin

Re: New engine: Stash

Post by mhouppin » Tue Mar 03, 2020 9:28 am

Gabor Szots wrote:
Tue Mar 03, 2020 8:52 am
Please tell me your country. The first set of tests with 9.0.1 is nearing its end and we put the author's nationality on our pages if it is available.
I'm French. I'm currently doing assets with compiled binaries for principal 64-bit architectures so that it becomes possible to use them without a compiler.
Thanks a lot for the tests ! ^^

PK
Posts: 857
Joined: Mon Jan 15, 2007 10:23 am
Location: Warsza
Contact:

Re: New engine: Stash

Post by PK » Tue Mar 03, 2020 9:49 am

Random movers are thousands of elo below a non-buggy basic AB engine.
Not only that, there is at least 600 Elo difference between a proper random mover and one that knows it pays off not to lose a queen.

Post Reply