Non-metric pairwise data with violations of symmetry, reflexivity or triangle inequality appear in fields such as image matching, web mining or cognitive psychology. When data are inherently non-metric, we should not enforce metricity as real information could be lost. The multidimensional scaling problem is addressed from a new perspective. I propose a method based on the h-plot, which natural...

A signed graph is a pair (G,Σ) where G is a graph and Σ is a subset of the edges of G. A circuit of G is even (resp. odd) if it contains an even (resp. odd) number of edges of Σ. A blocking pair of (G,Σ) is a pair of vertices s, t such that every odd circuit intersects at least one of s or t. In this paper, we characterize when the blocking pairs of a signed graph can be represented by 2-cuts i...

Two Cape Coloured siblings with typical features of Hurler's syndrome, but without mucopolysacchariduria or mucopolysaccharide accumulation in tissues, are presented. The clinical features, in conjunction with raised beta-D-galactosidase and alpha-L-fucosidase levels in fibroblast cultures from one of the patients, suggest the diagnosis of a mucolipidosis. Theories relating to the intracellular...