%0 Journal Article %T Cones of partial metrics %A Michel Deza %A Elena Deza %J Contributions to Discrete Mathematics %D 2011 %I University of Calgary %X A partial semimetric on a set X is a function $(x, y) mapsto p(x, y) in RR_{geq 0}$ satisfying $p(x, y) = p(y, x)$, $p(x, y) geq p(x, x)$ and $p(x, z) leq p(x, y) + p(y, z) p(y, y)$ for all $x, y, z in X$. We study here the polyhedral convex cone $PSMET_n$ of all partial semimetrics on $n$ points, using computations done for $n leq 6$. We present data on those cones and their relatives: the number of facets, of extreme rays, of their orbits, incidences, characterize ${0, 1}$- valued extreme rays, etc. %U http://cdm.math.ucalgary.ca/cdm/index.php/cdm/article/view/238