Title
Correlation of Boolean Functions and Pathology in Recursion Trees
Abstract
A Boolean function $f : \{0, 1\}^{n} \rightarrow \{0, 1\}$ is called trivial if it depends on only one coordinate. We show that nontrivial Boolean functions of positively correlated random variables are strictly less correlated than the variables themselves. This improves on a correlation inequality of Witsenhausen. Over the last decade, several people in computer science and computer chess have investigated the problem of quality and reliability in game-tree searching, where the heuristic evaluation function is not free of errors. In random models with independent leaf values and independently occuring errors, a phenomenon of pathology was observed: the deeper the search in the tree, the worse the final estimate of the root value. The main result of this note implies that pathology is not only a feature of game trees, but appears in any sequence of increasing bivalued recursion trees with independent leaf values, independently occuring errors, and nontrivial recursion rules.
Year
DOI
Venue
1995
10.1137/S0895480192240470
SIAM J. Discrete Math.
Keywords
Field
DocType
boolean function,recursion trees,nontrivial boolean function,boolean functions,nontrivial recursion rule,random model,computer chess,occuring error,heuristic evaluation function,computer science,bivalued recursion tree,independent leaf value,game trees
Boolean function,Discrete mathematics,Combinatorics,Random variable,Correlation inequality,Evaluation function,Game tree,Mathematics,Pathology,Recursion,Theory of computation,Search tree
Journal
Volume
Issue
ISSN
8
4
0895-4801
Citations 
PageRank 
References 
2
0.41
0
Authors
2
Name
Order
Citations
PageRank
Ingo Althofer121.08
Imre Leader226649.79