What was the last good Rodent?

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Ovyron
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What was the last good Rodent?

Post by Ovyron »

I have read a lot about the Rodent chess engine, regarding its playing style, and I finally got to test it. The Rodent III 0.287 version, to my disappointment.

So when I say "good", I'm talking about the playing style. The great thing about a playing style is that you don't need to play hundreds of games, a few are enough to showcase the style. Traditionally, I play 10 games with minimal books.

The first thing is to calibrate an opposing engine, so that you get results close to 50% performance. In this case, it looks like Wasp 3.60 at fixed depth 19 plays a bit stronger than Rodent at depth 20, so I used that (here's the PGN for collectors.)

I didn't see anything special about Rodent's style whatsoever in these games, just look at this game:

[pgn]1.g3 d5 2.Nf3 Nf6 3.Bg2 g6 4.d4 Bg7 5.Nc3 O-O 6.O-O Bf5 7.Ne5 c6 8.h3 Nbd7 9.g4 Be6 10.f4 Nb8 11.Qd3 Bc8 12.a3 Nbd7 13.Bd2 Qc7 14.Qf3 a5 15.Qf2 a4 16.Rae1 Qb6 17.Bc1 Qc7 18.Kh1 e6 19.e4 Nxe4 20.Nxe4 dxe4 21.Bxe4 c5 22.Be3 Nf6 23.Bg2 c4 24.d5 exd5 25.Bb6 Qb8 26.Bc5 Qc7 27.Bxf8 Kxf8 28.f5 gxf5 29.Qf4 Qc5 30.gxf5 Ra6 31.Re2 Qd6 32.Rd1 b5 33.Bf3 Bb7 34.Qg3 Bh8 35.Rg1 h6 36.Reg2 Ke7 37.Qh4 Qxe5 38.Re2 Qxe2 39.Bxe2 Kd7 40.Bf3 Ra8 41.Qxh6 Re8 42.h4 Bc6 43.Qf4 Kc8 44.h5 Ne4 45.h6 Rd8 46.Bxe4 dxe4 47.h7 e3+ 48.Kh2 e2 49.Qe3 Kb7 50.Qxe2 Bxb2 51.Rg8 Rd5 52.h8=Q Bxh8 53.Rxh8 Rd7 54.Qe5 Ka6 55.Qc5 Kb7 56.Rh6 f6 57.Rxf6 1-0[/pgn]

Very nice, huh? Except it was Wasp who was white :( I think black on this game is a good representation of what you'd expect to see from Rodent (9...Be6 10...Nb8 11...Bc8 12...Nbd7 :x ).

I know it has a couple dozen personalities and that some ought to blow me out the water, but I'd just think, what if some previous version of Rodent played as awesome as people praised it for by default, and the personalities would just enhance something already great?

Seeking help from people used to Rodent, do you know what was the last engine version with "the sparkle"?
Your beliefs create your reality, so be careful what you wish for.
pferd
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Re: What was the last good Rodent?

Post by pferd »

Opental gained quite a bit of attention for its style not too long ago. It is based on Rodent
http://www.pkoziol.cal24.pl/opental/

Disclaimer: Havent tried it myself...
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Ovyron
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Re: What was the last good Rodent?

Post by Ovyron »

pferd wrote: Sun Jul 28, 2019 9:46 pm Opental gained quite a bit of attention for its style not too long ago. It is based on Rodent
http://www.pkoziol.cal24.pl/opental/

Disclaimer: Havent tried it myself...
Thanks. Yeah, I tested OpenTal back when it was released and it was good stuff, but I hold if OpenTal's settings were applied on the most stylistic Rodent version (one that does it naturally) it'd play even better than OpenTal, if not as strong. Rodent III 0.287 probably has it in one of its personalities.
Your beliefs create your reality, so be careful what you wish for.
karger
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Re: What was the last good Rodent?

Post by karger »

Try Rodent Strangler personality ...
PK
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Re: What was the last good Rodent?

Post by PK »

I am aware that something went wrong with Rodent's style, probably because of automated tuning, and working to fix it. Noticed the problem watching CCRL game, a few elo weren't worth the mess it has been creating. However the good news is that if you set a personality, it uses mostly old default values, not new autotuned ones.

As for "the last stylish version", try https://github.com/nescitus/Rodent_III/ ... b_lite.zip or better
version 0.238
carldaman
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Re: What was the last good Rodent?

Post by carldaman »

PK wrote: Mon Jul 29, 2019 5:25 am I am aware that something went wrong with Rodent's style, probably because of automated tuning, and working to fix it. Noticed the problem watching CCRL game, a few elo weren't worth the mess it has been creating. However the good news is that if you set a personality, it uses mostly old default values, not new autotuned ones.

As for "the last stylish version", try https://github.com/nescitus/Rodent_III/ ... b_lite.zip or better
version 0.238
Thanks for the link, Pawel. It seems that the Texel auto-tuning method, while reliably increasing Elo, also does away with the intrinsic style of the engine. That's a questionable tradeoff, unless one's goal is more Elo at all costs.

Does the link posted point to v0.238? The files are from March 2017, but the version isn't specified.

I have also noticed that http://www.pkoziol.cal24.pl/rodent/rodent_history.htm gives a 404 error and then redirects away from your site.
carldaman
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Re: What was the last good Rodent?

Post by carldaman »

After doing some digging, I have concluded that the version linked by Pawel is probably Rodent III 0.172.
I don't seem to have v0.238, strangely enough. Can anyone please post a link to Rodent 0.238?
Thanks! :)
PK
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Re: What was the last good Rodent?

Post by PK »

Link is to version 0.172, as for 0.238 I'm afraid I will have to recomplile it.

BTW, I am slowly working on Rodent IV, and it's tuning system is already taking shape. There will be one interesting addition - "stylistic interpolation" between different sets of piece/square tables. Basically, you pick primary and secondary table set, and program interpolates between them, changing percentages slightly to fit its perception of the position (i.e. it increases weight for the set that seems to bring better score).
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Ovyron
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Re: What was the last good Rodent?

Post by Ovyron »

PK wrote: Mon Jul 29, 2019 5:25 am I am aware that something went wrong with Rodent's style, probably because of automated tuning, and working to fix it. Noticed the problem watching CCRL game, a few elo weren't worth the mess it has been creating.
Thanks Pawel. People caring about Strength should stick to Stockfish :D so, yeah, an engine that remains stylistic as it becomes stronger will be appreciated.
PK wrote: Mon Jul 29, 2019 5:25 am However the good news is that if you set a personality, it uses mostly old default values, not new autotuned ones.
Is there a personality that doesn't change anything and remains neutral but doesn't use autotuned values? I guess I'd want to set up that one.
PK wrote: Mon Jul 29, 2019 5:25 amAs for "the last stylish version", try https://github.com/nescitus/Rodent_III/ ... b_lite.zip or better
version 0.238
Heh, I was aware and spent a lot of time searching for 0.238 before settling with 0.287, because that was basically the only compiled one I could find...

It would be cool to have some "Rodent Archive" that includes all major releases (who knows if I'll end up going back to Rodent II for style? :mrgreen: )
Your beliefs create your reality, so be careful what you wish for.
carldaman
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Re: What was the last good Rodent?

Post by carldaman »

http://www.pkoziol.cal24.pl/rodent/history.htm contains a sampling of older Rodent versions. If Pawel can add v0.238 to it, that would be awesome. :)