We study the tournament fixing problem (TFP), which asks whether a tournament organizer can rig a single-elimination (SE) tournament such that their favorite player wins, simply by adjusting the initial seeding. Prior results give two perspectives of TFP: on the one hand, deciding whether an arbitrary player can win any SE tournament is known to be NP-complete; on the other hand, there are a nu...

We propose, to the best of our knowledge, the first Security Game where a Defender is supported by a spatially uncertain alarm system which non– deterministically generates signals once a target is under attack. Spatial uncertainty is common when securing large environments, e.g., for wildlife protection. We show that finding the equilibrium for this game is FNP–hard even in the zero–sum case a...

We present a heuristic matching algorithm for the generation of ground states of the short-range * J spin glass in two dimensions. It is much faster than previous heuristic algorithms. I t achieves near optimal solutions in time O( N ) in contrast to the best known exact algorithm which needs a time of O ( N S ” ) . From simulations with lattice sizes of up to 210 x 210 we confirm a phase trans...

This paper investigates two problems related to the determination of critical edges for the minimum cost assignment problem. Given a complete bipartite balanced graph with n vertices on each part and with costs on its edges, k Most Vital Edges Assignment consists of determining a set of k edges whose removal results in the largest increase in the cost of a minimum cost assignment. A dual proble...

The general Art Gallery Problem (AGP) consists in finding the minimum number of guards sufficient to ensure the visibility coverage of an art gallery represented by a polygon. The AGP is a well known NP-hard problem and, for this reason, all algorithms proposed so far to solve it are unable to guarantee optimality except in especial cases. In this paper, we present a new method for solving the ...

This paper presents an experimental study on several compaction algorithms for orthogonal drawings of graphs. We concentrate on algorithms that minimize the area, and compare them with other representative compaction algorithms in the state of the art. In particular, we propose a new exact algorithm that minimizes the total edge length subject to the optimization of the area, and experimentally...

In this paper we study the capacitated team orienteering problem where split deliveries are allowed. A set of potential customers is given, each associated with a demand and a profit. The set of customers to be served by a fleet of capacitated vehicles has to be identified in such a way that the profit collected is maximized, while satisfying constraints on the maximum time duration of each rou...

Many tasks in exploratory data mining aim to discover the top-k results with respect to a certain interestingness measure. Unfortunately, in practice top-k solution sets are hardly satisfactory, if only because redundancy in such results is a severe problem. To address this, a recent trend is to find diverse sets of high-quality patterns. However, a ‘perfect’ diverse top-k cannot possibly exist...

One of the problems arising in the analysis of biological sequences is the discovery of sequence similarity by finding common motifs. Several versions of the motif finding problem have been proposed for dealing with this problem and for each version, numerous algorithms have been developed. In this paper, we propose an exact algorithm, called SMS-H-FORBID to solve the Simple Motif Problem (SMP)...

It is shown that the traveling salesman problem for graphs of degree at most three with n vertices can be solved in time O(1.251), improving the previous bound O(1.260) by Eppstein.