Information-Geometric Equivalence of Transportation Polytopes
  This paper deals with transportation polytopes in the probability simplex (that is, sets of categorical bivariate probability distributions with prescribed marginals). Information projections between such polytopes are studied, and a sufficient condition is described under which these mappings are homeomorphisms. 
Mladen Kova\v{c}evi\'c, Ivan Stanojevi\'c, Vojin \v{S}enk
cs.IT math.CO math.IT