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| Zillions always shows the current value of a piece if you right-
| click on it. 

And apparently the positional value is included in this, as a Knight
clicked on g1 gives another score than when you cick it on f3? Does it
also report a different value for the Knight on g1 if you delete all Pawns
from both sides (turning the position from closed into open)? Does the
value of a Bishop clicked on f1 depend on if you delete the second
Bishop?

| It is easy to change the value by tweaking. Anyway, strategic piece 
| values are problematic. The bishop pair, in closed positions, holds 
| no advantage. 

It remains to be seen if this is due to a decrease of the B-pair bonus, or
simply a consequence of the drop of the Bishop base value in closed
positions cancelling the B-pair bonus. A lone Bishop is also inferior to a
lone Knight in closed position. Kaufman found that in GM play a Bishop is
worth 1/8 Pawn more than a Knight with 4 or fewer Pawns per side while
with 6 or more Pawns the Knight is 'slightly' stronger. Assuming that
the later would mean ~1/16 (I doubt he could see differences smaller than
that), it means the Bishop can lose 19 cP in a closed position, so 38 cP
for two of them. This is hardly less than the B-pair bonus.

| A knight is often more valuable than a bishop in closed positions. 
| A knight is regularly more valuable than a bishop in king + light 
| piece endgames when all pawns are on the same wing. I doubt Zillions 
| takes all this into consideration. This is Rybka stuff.

Well, end-games is a different matter. I agree tht to get accurate
empirical end-game values, you should actually use an engine that pays
attention to such details when generating the games. This is why I have
now started to design a variant-capable engine much stronger than
Fairy-Max (which is about the most minimalistic engine in existence). I
think most engines about 500 Elo below Rybka already pay attention to
things like this. 

But I would indeed be surprised if Zilions did. It should not be too
difficult to have a satisfactory general rule for this, upping the
Pawn-structure evaluation for spread Pawns if the opponent only has
short-range pieces. I doubt that Zillions has much Pawn-structure
evaluation in the first place. As I am mainly interested in piece values
in the context of normal Chess, with normal Pawns, I would like to do
these determinations with an engine that understands orthodox Pawns well
(scoring at least passers, (with bonuses for defended, or connected
passers), backward and isolated pawns.

| Together with Axiom, Zillions is quite powerful, although not very 
| strong. Axiom is a universal game engine that works in conjunction 
| with the Zillions of Games (ZoG) product. Specifically, Axiom consists
| of a ZoG plug-in DLL and a set of scripts written in the Axiom 
| language. Similar to the way in which the ZoG 'zrf' language is based

| on the Lisp language, the Axiom language is based on the Forth 
| language. Unlike ZoG, Axiom supports the ability for game developers 
| to specify the AI and therefore it has certain capacities that 
| Zillions lacks. 

Any sufficiently powerful language an be used to program an engine, and I
prefer to use plain C. Apparently the protocol used to interface between
the ZoG and its engines is an open standard. The problem is that people
have developed engines for this protocol, and adapters to connect WinBoard
engines to this protocol. But there are no alternative GUIs for this
protocol, or adapters that allow you to connect a ZoG engine to a standard
GUI. While (as far as I understood) it is actually the ZoG GUI that is most
wanting, as it is not able to play two different engines against each
other.