zurichess strength settings backwards...

[Harry Gostling]

Hi All, 

I was actually playing with Zurichess engine in Arena on my PC and i noticed that the play strength settings were the opposite that of Stockfish. Meaning the 0 - 20 is a "handicap", not "Skill Level" as with Stockfish.  So therefore level 20 is the weakest and 0 is the strongest.

Knowing that Zurchess is built into the Picochess system i thought I would take a look at Zurchess in Picochess and what i found is that indeed level 20 in Zurchess is in fact the weakest (unless i have some become a grand master)

So the reason for this note is to ask if its known that this is the way it works, i'm guessing not as Picochess just stated 'Level' (as it does with the Stockfish setting)  not 'handicap'.

Hope this makes sense. comment...

[Al]

Hi Harry,

Yes you are correct. The author of Zurichess coded his engine levels that way, as you discovered in Arena. So any build engine command would build it that way

For example, the e-zurich.uci file is like this:

[Level@00]
Handicap Level = 0

[Level@01]
Handicap Level = 1

[Level@02]
Handicap Level = 2

[Level@03]
Handicap Level = 3

[Level@04]
Handicap Level = 4

etc .... down to

[Level@20]
Handicap Level = 20

I’ve never tried it, but I guess it’s possible to edit the /opt/picochess/engines/armv7l/e-zurich.uci file and reverse the code like this:

[Level@00]
Handicap Level = 20

[Level@01]
Handicap Level = 19

[Level@02]
Handicap Level = 18

[Level@03]
Handicap Level = 17

[Level@04]
Handicap Level = 16

etc ... down to:

[Level@20]
Handicap Level = 0

This should put the weakest level to 0 and the strongest to 20, the same as our other Engines with levels.


Cheers,

Al.

[Harry Gostling]

Hi Al, 

Thanks for the confirmation.  I think your right transposing the file would fix it i think.  However my main thought is in the menu of picochess.  As it stands right now its say 'level' and it need to say 'handicap'  or if left with 'Level'  then the transposition of the file as you listed above needs to be built in as standard so every instance of the DGT Pi and Picohess is not incorrect. You agree?

Cheers
Harry.

[Jürgen Précour]

Hi (new) GM Harry Gostling,

I always knew using picochess making better chess players from all of us :-)

The author of this engine decided it so - i prefer it the other way around.
But Mr engine Al found a good(!) and easy solution to it...I would vote for changing the uci file for it to make Zurichess similar to the others.

Jürgen

[Al]

Hi Harry,

It’s really up to the Zurichess author to correct his Engine Levels. If we transpose the file like I suggested, this would be reverted every time someone builds the Engines again. (There’s a utility that automatically builds the engine-uci files and the engines.ini file based on each Engines UCI parameters)

Only Zurichess uses Handicap Level. Stockfish uses Skill Level, Texel uses Strength, Arasan & Galjoen use UCI_LimitStrength and Rodent & WyldChess use Personalities. As you can see there’s several different UCI options, we have to categorise these into 1 Option, so Level is the best option.

I suggest you do what’s best for you.


Cheers,

Al.

[Al]

Agh, it took me so long to type my last reply that Jürgen replied inbetween.

I agree with changing the file for all. Just beware of ever running build engines in future (Most people don’t use this anyway 😄)


Cheers,

Al.

[Harry Gostling]

Hi Al, Jurgen,

Thanks for the reply's, i'm cool with it tbh, i just wondered if you all knew, and you do.  I understand both sides and will live with it no problem.

Jurgen I'm very happy with the GM promotion ... its been a long time coming (hehe).... No seriously as someone who hovers around the 1500 mark i'm going to have long wait if ever, now i'm approaching 60 i fear I'll start my journey backward.

Cheers
Harry

[Jürgen Precour]

Hi Al,

to change the build script takes <1min...Any developer can do this. Perhaps should open an "easy issue" on github (since they asked for this to find more activate devs), aehm
Since i like yr idea, i did it already on my current code :-)

Jürgen

[Al]

Hi Jürgen,

Yeah me too. 😉

Al.