
PORTFOLIO THEORY: AN INTERNATIONAL PERSPECTIVE 471
s
m
= Standard deviation of the probability distribution of possible returns for the
market portfolio
(r
jm
s
j
) = Systematic risk (in absolute terms) of security j
b
j
= Systematic risk of security j in relative terms [(r
jm
s
j
)/s
m
]
Thus,
Expected return on security j = Risk-free return + Market risk premium
× Beta of security j
The SML (see Figure 15.4) describes the expected return for all assets/securities and portfo-
lios, efficient or not. The relationship between beta and expected return is linear. In other
words, the higher the beta for any security, the higher must be its expected ...