Properties of portfolios: risk 27
Multiple-asset portfolio
⎤ ⎥ ⎥ ⎥⎦
⎡ ⎢ ⎢ ⎢⎣
=
Σ
⎤ ⎥ ⎥ ⎥⎦
⎡ ⎢ ⎢ ⎢⎣
=
= ⋅ ⋅ ⋅ ⋅ =
∑
∑∑==
nn
n
n
n
j
i
n i
i
n j
i
j
i
P
x x
x
x
x
x
x
σ
σ
σ
σ
ρ
σ
σ
σ
"
#
%
#
"
#
1
1
11
1
,
11
2
,
'
Single-period random cash flows: Mean-variance portfolio theory