单个股票收益 Single Security return R=[D++(Pt-Po]Po E(R)=∑RP;(=1ton R;预期收益率 expected return P:预期收益的概率 probabilit! 7 of expected return For example E (R) 15%*0.25+10%0.5+8%*25=10.75% R=(1/M)*∑R1(=1ton)如果假设未来各年的收益都 相等 when all expected returns are same (R)3R=(15%+10%+8%)/3=11% 8-68-6 R=[Dt+(Pt -P0 )]/P0 E( R ) = ∑ RiPi (I=1 to n) Ri : 预期收益率 expected return Pi :预期收益的概率 probability of expected return For example: E( R ) = 15%* 0.25 +10%* 0.5 +8% *0.25 =10.75% R =(1/M)*∑ Ri (I=1 to n) 如果假设未来各年的收益都 相等 when all expected returns are same E( R ) =R =（15%+10%+8%）/3=11% 单个股票收益 Single Security Return