Semigraphoids Are Two-Antecedental Approximations of Stochastic
  Conditional Independence Models
  The semigraphoid closure of every couple of CI-statements (GI=conditional
independence) is a stochastic CI-model. As a consequence of this result it is
shown that every probabilistically sound inference rule for CI-model, having at
most two antecedents, is derivable from the semigraphoid inference rules. This
justifies the use of semigraphoids as approximations of stochastic CI-models in
probabilistic reasoning. The list of all 19 potential dominant elements of the
mentioned semigraphoid closure is given as a byproduct.
