Problem: Assume that security returns are generated by the single index model.
Ri = αi = βRM + ei
Where Ri is the excess return for security i and Rm is the market's excess return. The risk free rate is 4% 3
Suppose also that there are three securities A, B, and C, characterized by the following data.
|
Security
|
βi
|
E(Ri)
|
Α (ei)
|
|
A
|
0.8
|
15%
|
24%
|
|
B
|
1.1
|
18
|
15
|
|
C
|
1.4
|
21
|
18
|
a. If σM = 20%, calculate the variances of return of securities A, B, and C.
b. Now assume that there are an infinite number of assets with return characteristics identical to those of A, B, and C, respectively. What will be the mean and variance of excess return for securities A, B and C?