Heuristics are widely applied to modularity maximization models for the identification of communities in complex networks. We present an approach to be appli...

A branch and bound strategy is proposed for solving the clusterwise regression problem, extending Brusco's repetitive branch and bound algorithm (RBBA). The ...

We present a new column generation algorithm for the determination of a classifier in the two classes LAD (Logical Analysis of Data) model. Unlike existing a...

We study extremal graphs for the extremal values of the second largest <i>Q</i>-eigenvalue of a connected graph. We first characterize all simple connected g...

Normalized cut is one of the most popular graph clustering criteria. The main approaches proposed for its resolution are spectral clustering methods (e.g. [1...

Finding modules, or clusters, in networks currently attracts much attention in several domains. The most studied criterion for doing so, due to Newman and Gi...

An automatic method for constructing linear relaxations of constrained global optimization problems is proposed. Such a construction is based on affine and i...

Exact global optimization of the clusterwise regression problem is challenging and there are currently no published feasible methods for performing this clus...

In this paper we establish the definition of the <i>set of &epsilon;-proper equilibria</i> of a bimatrix game. We define a 0-1 mixed quadratic program to ge...

The main goal of this paper is to bring a contribution in order to facilitate automatic refinement of Bimatrix Game Nash extreme equilibria. We show how maxi...

Relationships between the diameter of a set of <i>n</i> points in the plane at mutual distance at least one, the diameter of an equilateral <i>n</i>-gon and ...

The modularity maximization model proposed by Newman and Girvan for the identification of communities in networks works for general graphs possibly with loop...

A new hierarchical divisive algorithm is proposed for identifying communities in complex networks. To that effect, the definition of <i>community in the weak...

Using the AutoGraphiX system, we obtain conjectures of the form <img src="/cgi-bin/mimetex.cgi?l(n) \leq q_1 \oplus i(G)\leq u(n)"> where <img src="/cgi-bin...

Let <i>G</i> be a connected graph of order <i>n</i>. The algebraic connectivity of <i>G</i> is the second smallest eigenvalue of the Laplacian matrix of <i>G...

The <i>proximity</i> <img src="/cgi-bin/mimetex.cgi?\pi = \pi (G)"> of a connected graph <i>G</i> is the minimum, over all vertices, of the average distance ...

We address the problem of locating in the plane objects such as segments, arcs of circumferences, arbitrary convex sets, their complements or their boundarie...

Harmonic means clustering is a variant of Minimum sum of squares clustering (which is sometimes called <i>K</i>-means clustering), designed to alleviate the ...

Variable neighborhood search (VNS) is a metaheuristic for solving combinatorial and global optimization problems whose basic idea is a systematic change o...

Let <i>Q = D + A</i> denote the signless Laplacian matrix of a graph <i>G</i> of order <i>n</i>, where <i>D</i> is the diagonal matrix of the degrees and <i...