Title
Computation Models for Parameterized Complexity
Abstract
A parameterized computational problem is a set of pairs [x, k], where k is a distinguished item called "parameter". FPT is the class of fixed-parameter tractable problems: for any fixed value of k, they are solvable in time bounded by a polynomial of degree alpha, where alpha is a constant not dependent on the parameter. In order to deal with parameterized intractability, Downey and Fellows have introduced a hierarchy of classes W[1] subset of or equal to W[2] subset of or equal to ... containing likely intractable parameterized problems, and they have shown that such classes have many natural, complete languages. In this paper we analyze several variations of the halting problem for nondeterministic Turing machines with parameterized time, and we show that its parameterized complexity strongly depends on some resources Like the number of tapes, head and internal states, and on the size of the alphabet. Notice that classical polynomial-time complexity fails in distinguishing such features. As byproducts, we show that parameterized complexity is a useful tool for the study of the intrinsic power of some computational models, and we underline the different "computational powers" of some levels of the parameterized hierarchy.
Year
DOI
Venue
1997
10.1002/malq.19970430204
MATHEMATICAL LOGIC QUARTERLY
Keywords
Field
DocType
turing machine,computational complexity,parameterized computational complexity
2-EXPTIME,PH,Discrete mathematics,DTIME,Computational problem,Parameterized complexity,Structural complexity theory,Combinatorics,Nondeterministic algorithm,Mathematics,Computational complexity theory
Journal
Volume
Issue
ISSN
43
2
0942-5616
Citations 
PageRank 
References 
12
1.33
3
Authors
2
Name
Order
Citations
PageRank
Marco Cesati118512.53
Miriam di Ianni214417.27