With the position tree, the program offers a powerful tool for opening training. You can use a position tree not only as an openings book but, thanks to the transparent display of information, also excellently for your own opening training.
The principle
In a position tree all moves are linked. The strength of the concept is that the position tree shows the user a concrete evaluation of the possible continuations for any position. With the help of the position tree it is therefore particularly easy to get an overview of the quality of certain opening trends and continuations. A decisive criterion for the practical value of the position tree is, above all, the quality of the games from which it was generated. It should be obvious that scepticism is in order when interpreting the statistics of individual continuations if, for example, games from the most recent youth championships have flowed into the position tree.
The PowerBook
On the PowerBook DVD-ROM you will find a position tree based on over 1 million games. This position tree is based on particularly carefully selected, high-quality games and represents the current state of opening theory. The game database used as the basis for the tree is by the way included in delivery. Using the database you can convince yourself that only high-quality games by strong players were used as the basis for the new position tree.
Tip: The PowerBook requires, due to the numerous embedded information, around 1 GB of hard disk space. That is not exactly little, so there is the option to work with the tree directly from the DVD. Ideally, however, you should copy the tree to the hard disk and operate it from there. On the one hand, access to the tree is much faster, and on the other hand the learning function of Deep Fritz & Co can reset the book preferences.
Pure information!
You can of course use the position tree not only for statistical analyses of the value of particular opening systems but also use the tree directly as the opening library under the program. Let us look once, using the PowerBook 2002 as an example, how the information and notes of the position tree are to be interpreted under the program.
Tip: Unlike the predecessor versions, it is not necessary to switch to a special view mode in order to see the statistical displays. You can switch between notation and tree view with the TAB key.
Now let us take a closer look at the display of the PowerBook.
Switch on the entry Properties via the context menu. You can now set some specifications regarding how the information is displayed on the screen. Make sure to activate the Statistics switch in order to switch on the small instructive bar graphic under the position tree. The small, instructive bar graphic under the move list rounds off the information content ideally. At a glance, you can visually get an impression of the success prospects of a particular move or variation.
From the initial position, the display looks as follows:
• N = the initial position appears in the position tree 628 163 times. Logical: the tree was generated on the basis of 628 163 games.
• % = from the initial position, White achieved 55%. This value underlines the thesis of White's slight first-move advantage in the initial position.
• AV = the average Elo is 2413 points
• Perf = White achieved an average performance of 2447 Elo points
• The entries Fritz and Prob relate to playing behaviour when the tree is used as an opening library under the program. You will notice that the display changes (adapts) and updates each time you select a particular continuation.
Tip: Navigation in the tree window is best carried out with the arrow keys. Arrow up/down switches between the moves. Arrow right (or mouse click) executes a move, Arrow left undoes the move.
Question: Why are some entries in the position tree displayed in grey text? If an entry could be statistically less meaningful due to certain factors, this is specifically indicated by grey text. Example: If the number of games in the Result section is relatively small, this could negatively affect a final assessment.
The upper and the lower bar represent winning or losing games respectively; the middle bar stands for drawn games. If the middle bar is very long in relation to the other bars, this signals at a glance a high draw rate. This function is also very well suited to verifying certain questions or assessments about a particular variation. Let us look at this with a concrete example.
Many chess friends assume that the Sicilian Defence is a particularly combative opening with a low tendency to draws. A glance at the position tree teaches us that, on the basis of the games imported into the position tree, this assessment is not necessarily correct.
34% of the games ended with a peaceful sharing of points after all! Otherwise, you immediately see that in this opening White has marginally better success prospects than the second player and that this opening offers both sides very favourable perspectives.