On the parameterized complexity of monotone and antimonotone weighted circuit satisfiability.

We consider the weighted monotone and antimonotone satisfiability problems on normalized circuits of depth at most t≥2, abbreviated Image 1 and Image 2, respectively, where the parameter under consideration is the weight of the sought satisfying assignment. These problems model the weighted satisfiability of monotone and antimonotone propositional formulas, and serve as the canonical problems in the definition of the parameterized complexity hierarchy. Moreover, several well-studied problems, including important graph problems, can be modeled as Image 1 and Image 2 problems in a straightforward manner.