Asset market ·CAPM: Mean-variance efficient: minimize the Variance when the means are same min∑∑xxom a=0b=0 ∑x2R=R ∑Asset market • CAPM: – Mean-variance efficient: minimize the Variance when the Means are same. 0 0 0 0 0 min . . 1 A A A a b ab x x a b A a a a A a a x x s t x R R x  = = = = = =    