Hi Derek, concerning the differences of our piece value models let me
repeat to mention, that I later will work out a refined approach, where
piece values (more precisely their mobility part) will depend on the
percentage of free squares on the board. It could be then, that in
practical games that could even more hide those theoretically existing
differences. And I repeat to point out, that as pieces were exchanged not
only their average piece values will be removed from the board but also
their positional influences. My program SMIRF puts that all together when
calculating the new evaluation after an exchange. Thus it is not
convincing to focus merely on average piece value differences.
When I see, that here a discussion is running on evaluating other game
pieces, let me add some thoughts. Chess is an inertial game, that means,
its evaluation is changing slowly through the game, despite of tactical
errors. There are other games like Shogi, where more dynamic elements are
changing that kind of lazyness. Watching evaluation trees there leads to
instable search results, finally having some kind of a randomly generated
value overlay. In other words, the evaluation does not that much depend on
average piece values as compared to Chess, but instead much more on
surprisingly rising tactical occurrences. Also CRC may be positioned a
small step nearer to that behaviour seen from Chess.
During the last days I also have thought over the problem on how to create
a meaningful evaluation model for the game of Arimaa, which will be
extremely different from Chess. I have seen there on its discussion site
how people are trying to establish position depending piece values. But I
doubt that this would be a promising way to do that job. Actually I
believe, that pieces interdepending constellations there are much more
important than such an elementary try.