In this paper, two interesting complexity classes, PP and P, are compared with PH, the polynomial-time hierarchy. It is shown that every set in PH is polynomial-time Turing reducible to a set in PP,â€¦ (More)

In this paper, it is shown that many natural counting classes, such as PP, C=P, and MODkP, arc at least as computationally hard as PH (the polynomial-time hierarchy) in the following sense: for eachâ€¦ (More)

The main purpose of this paper is to exhibit non-algebraic problems that are computationally equivalent to computing the integer determinant. For this purpose, some graph-theoretic counting problemsâ€¦ (More)

The existence of setsnot being â‰¤ tt P -reducible to low sets is investigated for several complexity classes such as UP, NP, the polynomial-time hierarchy, PSPACE, and EXPTIME. The p-selective setsâ€¦ (More)

The intractability of the complexity class NP has motivated the study of subclasses that arise when certain restrictions on the definition of NP are imposed. For example, the study of sparse sets inâ€¦ (More)

We investigate the computational power of the new counting class ModP which generalizes the classes ModpP p prime We show that ModP is polynomial time truth table equivalent in power to P and thatâ€¦ (More)

In this paper, PF(#P) is characterized in a similar manner to Krentelâ€™s characterization [I<re88] of PF(NP). Let MidP be the class of functions that give the medians in the outputs of metric Turingâ€¦ (More)