Author: chandler yergin
Date: 02:46:11 05/19/05
This maybe a good time to reflect on what the Analysis Module & Engine is really doing; and what the Opening Trees really are. The Opening Tree consists of positions, not games. For every position in the Tree, the Program can display what moves have been played, how often, by whom, and what level of success they have had. The statistical % is used by the Program when out of book. It can be misleading, and I think Dann Corbit covered this in his Post, when he indicated that a move might reflect an average score of 70%, but this % comes from older games. or, the line may have been abandoned when a refutation was found. Unless the Database is constantly updated, by new games, the latest in Theory will be missing. The advantage in studying Openings using the Tree, is that there are no transposition problems. The moves or move order used to reach the position is irrelevant. There are some that seem to be confused about what the Analysis module and Engine is doing; so I address this to them. If any Programmers can add to this, I welcome your comments. At any time in any position, the Analysis module will examine and evaluate every possible move 1/2 Ply at a time. Example: Many times on CCC a position or FEN is given, and the Question asked.. "How long does it take for your engine to 'find' such and such a move?" This is misleading.. as the Engine has already found it almost instantly. You just aren't seeing it, because you are "Scrolling" only the PV! If the Postion has 20 'possible' moves; the Module has 'evaluated' 20 PV's Simultaneously, and ranked them in order of 'best' move first. It will do this continually 1/2 Ply at a time. Each time is one iteration. The more 'possible moves' there are, the more time it takes for each iteration as the depth of search goes deeper, the Tree gets larger. All the Module or engine is doing is "Evaluating", based on static positional factors which are programmed in. Material, King safety, Space, strong and weak squares, the 2 Bishop advantage, Pawn structure, Open files, half open files, and many other factors the Programmers feel are important. THere is also a learning algorithm where the Program can learn from it's mistakes, and is self correcting in that regard. I can only speak of my experience with Chessbase; some of you have Bookup or other Database Programs. In Chessbase 9 for example, when I want to analyze a position, I Open Chessbase 9, Open a Board, insert the Fen, and Start an Analysis Module. The nice thing about this is, that I can Clip and Paste the entire Analysis into a word Processor or CCC POst with Diagram. It shows exactly the Iterations, time, eval, etc.. Many here use only the Engine EVals which they "Cut & Paste" and it does not show the detail of what the Engine is doing. The Opening Tree is really very shallow, and the Program gets 'out of book' early. In these cases, it is usually in the middle to late Opening phase where there are many 'possible' positions. This is where the time factor is critical. When playing against the engine in these situations, many times, the "best" move is far below the horizon and the Program cannot see it. This is where the Top PLayers shine... and get their advantage. Under Tournament time controls, the Time allocation software determines when the Program must move. If the time is 40 moves in 2 hours, the average time for each move for the Program is 3 minutes. As you can see, this is often not enough, and the Program may make what looks like strange moves. It may see that in 40 Ply, it will have a serious disadvantage, and will sac pieces just to postpone the inevitable. Endgame Table Bases give the Program 'exact' play. It also makes them make strange moves. I have seen the Program give up a Queen, simply to get into the EGTB's. This is certainly not human behavior, but is typical of Computers. Another interesting point I might make is the Opening Tree that comes with the Program. Earlier I mentioned that the Tree uses Statistical information from the number of games played, and the success rate of the moves. This can be very misleading.. for example; The Urusov Opening. The statistics are very much in favor of Black! Well.. only because it is seldom played; and most of the White PLayers, including Steintz & Lasker had blundered. Lasker lost in 7 moves I think, Steintz did not do much better. If you want to perform an interesting experiment, Open the Database Program.. Open the Tree, start your analysis module, browse through the Tree, and watch the Evaluations.. What may look as 'winning' for one move, can turn into a disaster on the next! I'd be interested in any and all comments, and your own personal experiences with Databases, Engines, etc. if you'd care to share. Some may have some good ideas on how best to use the Computer to study Openings. Correspondence players for sure. I'm sure Komputer Korner would appreciate it too.. Thanks for listening, Chan
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