  The main objective is to present a some variant of the Black - Litterman
model. We consider the canonical case when priori return is determined by means
such excess return from the CAPM market portfolio which is derived using
reverse optimization method. Then the a priori return is at risk quantified
uncertainty. On the side, intensive discussion shows that the experts' views
are under knightian uncertainty. For this reason, we propose such variant of
the Black - Litterman model in which the experts' views are described as
intuitionistic fuzzy number. The existence of posterior return is proved for
this case.We show that then posterior return is an intuitionistic fuzzy
probabilistic set.
