Some Typical Properties of Large AND/OR Boolean Formulas

In this paper typical properties of large random Boolean AND/OR formulas are investigated. Such formulas with n variables are viewed as rooted binary trees chosen from the uniform distribution of all rooted binary trees with m leaves, where n is fixed and m tends to infinity. The leaves are labeled by literals and the inner nodes by the connectives AND/OR, both uniformly at random. In extending the investigation to infinite trees, we obtain a close relation between the formula size complexity of an arbitrary Boolean function f and the probability of its occurrence under this distribution, i.e., the negative logarithm of this probability differs from the formula size complexity of f only by a polynomial factor.

[1]  Yuval Rabani,et al.  A computational view of population genetics , 1995, STOC '95.

[2]  Ravi B. Boppana,et al.  Amplification of probabilistic boolean formulas , 1985, 26th Annual Symposium on Foundations of Computer Science (sfcs 1985).

[3]  Petr Savický Improved Boolean Formulas for the Ramsey Graphs , 1995, Random Struct. Algorithms.

[4]  Avi Wigderson,et al.  Quadratic dynamical systems , 1992, Proceedings., 33rd Annual Symposium on Foundations of Computer Science.

[5]  Leslie G. Valiant,et al.  Short Monotone Formulae for the Majority Function , 1984, J. Algorithms.

[6]  Jeff B. Paris,et al.  A Natural Prior Probability Distribution Derived from the Propositional Calculus , 1994, Ann. Pure Appl. Log..