Null Move Observation
Null Move Observation,
the observation that for the side to move there is almost always a better alternative (move) than doing nothing. The Null Move Observation might be considered as tempo bonus in evaluation, but it fails in Zugzwang situations.
The Null Move Observation is base of:
- Null Move Pruning
- Null Move Reductions
- Fail-High Reductions
- Reverse Futility Pruning
- Standing Pat in Quiescence Search 
- Gordon Goetsch , Murray Campbell (1988). Experimenting with the Null Move Heuristic in Chess. AAAI Spring Symposium Proceedings, pp. 14-18.
- Don Beal (1989). Experiments with the Null Move. Advances in Computer Chess 5, a revised version is published (1990) under the title A Generalized Quiescence Search Algorithm. Artificial Intelligence, Vol. 43, No. 1, pp. 85-98. ISSN 0004-3702, edited version in (1999). The Nature of MINIMAX Search. Ph.D. thesis, IKAT, ISBN 90-62-16-6348. Chapter 10, pp. 101-116
- Don Beal (1990). A Generalized Quiescence Search Algorithm. Artificial Intelligence, Vol. 43, No. 1, pp. 85-98. ISSN 0004-3702
- Rainer Feldmann (1997). Fail-High Reductions. Advances in Computer Chess 8, available as pdf from CiteSeerX
- Don Beal (2006). Review of a nullmove-quiescence search mechanism from 1986. File:Alg1986review.txt (Draft)