Check out Janggi (Korean Chess), our featured variant for December, 2024.

Enter Your Reply

The Comment You're Replying To
H. G. Muller wrote at 12:51 PM UTC in reply to Dmitry Eskin from 06:23 AM:

Before the use of Neural Networks for evaluation became common, the strongest chess programs all used two sets of piece values (as well as for some other parameters, like passed-pawn bonuses, mobilities...), referred to as 'opening values' and 'end-game values'. Two evaluations are then made based on these, and the actual evaluation is then calculated by linear interpolation of these as a function of 'game phase'. The latter is based on the (weighted) number of pieces present, e.g. 4*queens + 2*rooks + minors or 6*queens + 3*rooks + minors. (Pawns are usually ignored; if anything these should probably have negative weight.)

Systematic increase of piece values towards the end-game, without changing their ratio, would encourage even equal piece trading when ahead (to advance the game phase).

Fairy-Max doesn't have such an advanced evaluation. But in my experience moderate misconceptions about the piece values are not affecting the outcome of material-imbalance games much. As long as both players share the same misconception.

To get piece values for later in the game, you could start material-imbalance games from early end-game positions. E.g. with each player 4-6 pawns in a symmetric setup and 1-3 (non-royal) pieces. This is a bit more tricky, since the shorter remaining game duration leaves less rooms for the players to make errors. So an extra Pawn might already be enough to produce a 100% win rate, making it impossible to estimate how large the advantage actually was. randomizing the first few moves might no longer make it possible to get a little more spread-out results. I guess this could be cured by averaging over a large number of different, not necessary symmetric pawn structures used as starting positions.

I once did a test for Archbishop vs Rook + Knight as only pieces in the presence of 4-6 Pawns, and the Archbishop still came out on top. Even with an extra Pawn for the R+N it could often beat them. So I am skeptical about the Archbishop value going down in the end-game.

The anomalously high value of the Archbishop seems for a large part a result of its power to destroy Pawn chains. This might be coupled very much with how Pawns move. In general piece values are also dependent on the detailed material composition of the opposing army, rather than just on a global measure of its total strength. E.g. 3 Queens vs 3 Queens (in the presence of equal Pawns) would obviously be equal, but 3 Queens lose very badly to 7 Knights. Despite the fact that conventional piece values predict 3 Queens to balance 9 Knights.

So that you observe the value of Archbishops to go down towards the end-game might also be due to using it in a different-armies setting, with different Pawn types. Perhaps it loses the effectivity that is exhibits against FIDE Pawns, and this would hurt more in the end-game. Where the ratio Pawns vs pieces usually goes up. (The stronger the pieces, the earlier they usually get traded out of the game.)


Edit Form

Comment on the page Asymmetric Chess

Conduct Guidelines
This is a Chess variants website, not a general forum.
Please limit your comments to Chess variants or the operation of this site.
Keep this website a safe space for Chess variant hobbyists of all stripes.
Because we want people to feel comfortable here no matter what their political or religious beliefs might be, we ask you to avoid discussing politics, religion, or other controversial subjects here. No matter how passionately you feel about any of these subjects, just take it someplace else.
Avoid Inflammatory Comments
If you are feeling anger, keep it to yourself until you calm down. Avoid insulting, blaming, or attacking someone you are angry with. Focus criticisms on ideas rather than people, and understand that criticisms of your ideas are not personal attacks and do not justify an inflammatory response.
Quick Markdown Guide

By default, new comments may be entered as Markdown, simple markup syntax designed to be readable and not look like markup. Comments stored as Markdown will be converted to HTML by Parsedown before displaying them. This follows the Github Flavored Markdown Spec with support for Markdown Extra. For a good overview of Markdown in general, check out the Markdown Guide. Here is a quick comparison of some commonly used Markdown with the rendered result:

Top level header: <H1>

Block quote

Second paragraph in block quote

First Paragraph of response. Italics, bold, and bold italics.

Second Paragraph after blank line. Here is some HTML code mixed in with the Markdown, and here is the same <U>HTML code</U> enclosed by backticks.

Secondary Header: <H2>

  • Unordered list item
  • Second unordered list item
  • New unordered list
    • Nested list item

Third Level header <H3>

  1. An ordered list item.
  2. A second ordered list item with the same number.
  3. A third ordered list item.
Here is some preformatted text.
  This line begins with some indentation.
    This begins with even more indentation.
And this line has no indentation.

Alt text for a graphic image

A definition list
A list of terms, each with one or more definitions following it.
An HTML construct using the tags <DL>, <DT> and <DD>.
A term
Its definition after a colon.
A second definition.
A third definition.
Another term following a blank line
The definition of that term.