We survey and compare parameterizations of the propositional satisfiability problem (SAT) in the framework of Parameterized Complexity (Downey and Fellows, 1999). In particular, we consider (a) parameters based on structural graph decompositions (tree-width, branch-width, and clique-width), (b) a parameter emerging from matching theory (maximum deficiency), and (c) a parameter defined by transl...

Rotation distance between trees measures the number of simple operations it takes to transform one tree into another. There are no known polynomial-time algorithms for computing rotation distance. In the case of ordered rooted trees, we show that the rotation distance between two ordered trees is fixed-parameter tractable, in the parameter, k, the rotation distance. The proof relies on the kern...

We present an algorithm with runtime O(knm) for the following NP-complete problem [9, problem GT35]: Given an arbitrary graph G on n vertices and m edges, can we obtain an interval graph by adding at most k new edges to G? This resolves the long-standing open question [17, 7, 25, 14], first posed by Kaplan, Shamir and Tarjan, of whether this problem was fixed parameter tractable. The problem ha...

Minimizing a cost function under a set of combinatorial constraints is a fundamental, yet challenging problem in AI. Fortunately, in various real-world applications, the set of constraints describing the problem structure is much less susceptible to change over time than the cost function capturing user’s preferences. In such situations, compiling the set of feasible solutions during an offline...

The train marshalling problem is about reordering the cars of a train using as few auxiliary rails as possible. The problem is known to be NP-complete. We show that it is fixed parameter tractable (FPT) with the number of auxiliary rails as parameter.

Abstract argumentation frameworks have received a lot of interest in recent years. Most computational problems in this area are intractable but several tractable fragments have been identified. In particular, Dunne showed that many problems can be solved in linear time for argumentation frameworks of bounded tree-width. However, these tractability results, which were obtained via Courcelle’s Th...

To enumerate 3-manifold triangulations with a given property, one typically begins with a set of potential face pairing graphs (also known as dual 1-skeletons), and then attempts to flesh each graph out into full triangulations using an exponential-time enumeration. However, asymptotically most graphs do not result in any 3-manifold triangulation, which leads to significant “wasted time” in top...

One of the goals of Artificial Intelligence is to create autonomous software agents which exhibit social intelligence, i.e are capable to act as a group member in various groups and, in particular, to participate in group decision making. For such agents to be programmed we need protocols which are formalizable. In this paper we are suggesting such a protocol based on one of the most famous and...

The family of judicious partitioning problems, introduced by Bollobás and Scott to the field of extremal combinatorics, has been extensively studied from a structural point of view for over two decades. This rich realm of problems aims to counterbalance the objectives of classical partitioning problems such as Min Cut, Min Bisection and Max Cut. While these classical problems focus solely on th...

The firefighter problem is defined as below. A fire initially breaks out at a vertex r on a graph G. In each step, a firefighter chooses to protect one vertex, which is not yet burnt. And the fire spreads out to its unprotected neighboring vertices afterwards. The objective of the problem is to choose a sequence of vertices to protect, in order to save maximum number of vertices from the fire. ...