Fritz 21 Handbook

Alpha-Beta

Contents
Contents

This describes a technique that leads to a dramatic increase in search depth. When pre-calculating a move, large parts of the search tree are "pruned". Certain move sequences are simply ignored, ideally without affecting the result. The principle of this technique is based on the fact that a move does not have to be examined completely if a better move is already known.

If the program detects that the move currently being analysed is worse than the most favourably evaluated alternative known so far, it does not have to be examined further. The Alpha-Beta algorithm has contributed significantly to the increase in the playing strength of chess engines.

1
2
2.1
Ribbons
2.2
The menu bands
2.3
2.4
2.5
Style specifications
2.6
Board design – 2D board
2.7
Board window navigation
2.8
User Info
2.9
2.10
2.11
2.12
2.13
2.14
2.15
2.16
2.17
New board sounds
2.18
Style variants
3
3.1
3.2
3.3
3.4
3.5
3.6
3.6.1
Enter & Analyse
3.6.2
Evaluation of the position
3.6.3
Analysis with the Buddy Engine
3.6.4
FAQ Buddy Engine
3.6.5
Visualize engine analysis
3.6.6
Visual Evaluation
3.6.7
Evaluation history in the search
3.6.8
Different displays in the engine window
3.6.9
Full analysis / Tactical Analysis
3.6.10
A tip for Full analysis
3.6.11
Infinite analysis
3.6.12
Duration analysis with analysis comments
3.6.13
Example Tactical Analysis
3.6.14
Deep position analysis
3.6.15
Blundercheck
3.6.16
Using engines interactively
3.6.17
Blitz & train on Playchess.com
3.6.18
Training questions
3.6.19
Commentary symbols in the Fritz Blunder search
3.6.20
Compare analysis
3.6.21
Automatic analysis of server games
3.6.22
Shootout
3.6.23
The Kibitzer
3.6.24
Parallel analysis
3.6.25
Monte Carlo
3.6.26
Extended Engine Information
3.6.27
3.6.28
3.6.29
3.6.30
The Analysis board
3.6.31
Variation board
3.6.32
Visualize Search
3.6.33
Animated engine variants
3.6.34
Chess problems, mate search
3.6.35
Mate search with Fritz
3.6.36
Tips in the engine window
3.6.37
Calculating Elo ratings retrospectively
3.7
3.8
3.9
3.10
3.11
3.12
4
5
6
Glossary
Entering DGT board positions
Analysis mode
1
2
2.1
Ribbons
2.2
The menu bands
2.3
2.4
2.5
Style specifications
2.6
Board design – 2D board
2.7
Board window navigation
2.8
User Info
2.9
2.10
2.11
2.12
2.13
2.14
2.15
2.16
2.17
New board sounds
2.18
Style variants
3
3.1
3.2
3.3
3.4
3.5
3.6
3.6.1
Enter & Analyse
3.6.2
Evaluation of the position
3.6.3
Analysis with the Buddy Engine
3.6.4
FAQ Buddy Engine
3.6.5
Visualize engine analysis
3.6.6
Visual Evaluation
3.6.7
Evaluation history in the search
3.6.8
Different displays in the engine window
3.6.9
Full analysis / Tactical Analysis
3.6.10
A tip for Full analysis
3.6.11
Infinite analysis
3.6.12
Duration analysis with analysis comments
3.6.13
Example Tactical Analysis
3.6.14
Deep position analysis
3.6.15
Blundercheck
3.6.16
Using engines interactively
3.6.17
Blitz & train on Playchess.com
3.6.18
Training questions
3.6.19
Commentary symbols in the Fritz Blunder search
3.6.20
Compare analysis
3.6.21
Automatic analysis of server games
3.6.22
Shootout
3.6.23
The Kibitzer
3.6.24
Parallel analysis
3.6.25
Monte Carlo
3.6.26
Extended Engine Information
3.6.27
3.6.28
3.6.29
3.6.30
The Analysis board
3.6.31
Variation board
3.6.32
Visualize Search
3.6.33
Animated engine variants
3.6.34
Chess problems, mate search
3.6.35
Mate search with Fritz
3.6.36
Tips in the engine window
3.6.37
Calculating Elo ratings retrospectively
3.7
3.8
3.9
3.10
3.11
3.12
4
5
6
Glossary