We describe three applications in computational learning theory of techniques and ideas recently introduced in the study of parameterized computational complexity. (1) Using parameterized problem reducibilities, we show that P-sized DNF (CNF) formulas can be exactly learned in time polynomial in the number of variables by extended equivalence queries if and only if the dominating sets of a graph can be learned in polynomial time by extended equivalence queries. (That is, learning by an arbitary hypothesis class. See Angluin [?].) Since learning dominating sets is a special case of learning monotone CNF formulas, this extends to the exact learning model a result of Kearns, li, Pitt and Valiant in the PAC prediction model [?]. We show that P-sized DNF (CNF) formulas can be learned exactly in polynomial time by extended equivalence and membership queries if and only there is an algorithm running in time polynomial in n and k to learn the k element dominating sets of an n vertex graph. We...
Rodney G. Downey, Patricia A. Evans, Michael R. Fe