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View Full Version : Thinking Lines, etc

echrise224
08-17-2004, 06:33 PM
I really think that the Chessmaster rulebook/glossary doesnt go over the features very well. Another case in point: thinking lines. What is this time, depth and score. What is a depth 2/4 mean. What does a -4.30 score mean. I am clueless what this all about. Can some let me know what this mean and guide me in the right direction where to find out a place to find out what these depth/score numbers mean. Even in the graph mode a -9999 for black doesnt mean to much to me. What does that number mean to me? Thanks guys for your help.

echrise224
08-17-2004, 06:33 PM
I really think that the Chessmaster rulebook/glossary doesnt go over the features very well. Another case in point: thinking lines. What is this time, depth and score. What is a depth 2/4 mean. What does a -4.30 score mean. I am clueless what this all about. Can some let me know what this mean and guide me in the right direction where to find out a place to find out what these depth/score numbers mean. Even in the graph mode a -9999 for black doesnt mean to much to me. What does that number mean to me? Thanks guys for your help.

RMcCrea
08-17-2004, 08:10 PM
First off, let me say the depth is practically irrelevant to a typical hobbiest who wants to play chess. Evalutation is meaningful, but I don't know why they use a non-traditional scale in the game graph, where they do you the typical scale for the thinking lines.

depth 2/4 probably means it's currently working looking at moves 2 ply (half-moves) deep. The furthest it has looked is 4 ply deep.

so lets say without using an opening book, a computer personality is looking at the starting poistion. Depth 2/4 may mean is currently looking 2 moves deep. It's already considered 1.a3, 1.a4, 1.Na3, and all other white moves since thats one ply. After looking at one ply, maybe it favored 1.e4, 1.d4 and 1.c3. (just for sake of example). Then it moved on to the 2nd ply. It briefly considers 1.e4 a6, 1.e4 a5, 1.e4 Na6, 1.d4 a6, 1.d4 a5, 1.d4 Na6, 1.c4 a6, 1.c4 a4, 1.c4 Na6, and all the other combinations based upon the moves it considered "intresting" from it's examination of the first ply. That explains the first number, it is considering these 2nd moves. The second number, "4" in your example, would be how far it has looked. When considering 1.f3, perhaps it evaluated 1.f3 e5 2.g4 Qh4#, and decided it was bad, and thus has discarded 1.f3. But that line it considered is 4 plys, and it considered some positions 4 plays deep so far.

Again, 2/4 means it's working on considering all of the 2nd ply moves. 4 means that so far while considering these moves, it has look 4 plys deep. Point being that even at depth of 1 ply, it doesn't just look at the position after a move, it considers probable lines that move will lead to, before it rules out, or holds onto that move for further consideration.

Eavaluation is based on one point for a pawn, and 100 points being winning.

Evaluation examples: 1.00 "White is up a pawn, [or has positional superiority worth the value of a pawn, if both side play perfectly as far as chessmaster can see.]"
-1.00 "White is down a pawn."
-5.00 "Black is ahead by a rook."
+9.00 "Black is a queen down."
+12.00 "White's ahead by a bunch of material" (I seem to see 12 or so alot when it's clear that I will promote a pawn in a easily won position")
-27.00 "Black probably won't lose."
=0.00 "Looks like a draw".

Now, this would be easier if it only considered material, but It also considers positional aspects, which you can control in the custom personalities: Nonstandard material values, king safety, space, control of the center, piece mobility, pawn weakness, etc.

Just like a situation where Waitzking may say, "white is down a pawn, but his superior development provides ample compensation" -- Chessmaster may give white a "slight advantage" by evaluating this situation as +0.30 -- literally designed to mean "white is ahead by three tenth of the value of a pawn."

Whew, that's all I want to type for now.

I think the graph is a poor idea, especially while it only has move numbers instead of the moves -- just not practical to flip between game moves and the graph. I'd suspect that the 9999 represents checkmate, or a score or 99.99 as traditional chess engines would use. -- But I'm not going to check.

Peace Out.

EddiePX
08-17-2004, 11:05 PM
99xx values are most certainly mate opportunities (forced mate possible in 99-xx moves; for example, 9997 means that mate in 2 is possible).

echrise224
08-18-2004, 06:21 AM
Whow thanks guy. So they are looking basically 4 moves ahead? What is a half move? Dont really see that displayed.

Maybe on the graph chart we can have a patch to better explain those numbers so they can be more meaniful to the average player.

The score thing now makes more sense since its based on positional move/score. This would also be nice if they explain the score/positional placement in a more common English format. Add this to the post analysis of the game. Can Chessmaster do this? I have for years been clammoring for them to explain those depths and score and in an English narrative to give you a depth and breathe on how well or poor you did. They do an overall good job of post analysis just make those depths/scores more plausible and understandible to the average fan.

Make sense? A possible patch for these things above or we have to wait until the 11th edition.