The expected return and
standard deviation of SugarKane is now
E(rSugarKane) (.5
7) .3( 5) (.2
20) 6
SugarKane
[.5(7 6)2 .3( 5
6)2 .2(20 6)2]1/2
8.72
The covariance between the
returns of Best and SugarKane is
Cov(SugarKane, Best) .5(7
6)(25 10.5) .3( 5
6)(10 10.5)
.2(20
6)( 25 10.5)
90.5
and the correlation coefficient
is
Cov(SugarKane, Best)
(SugarKane, Best)
SugarKane
Best
90.5 .55
8.72 18.90
The correlation is negative,
but less than before ( .55 instead of
.86) so we expect that SugarKane will now be
a less powerful hedge than before. Investing
50% in SugarKane and 50% in
Best will result in a portfolio probability distribu- tion of
Probability .5 .3 2
Portfolio return 16 2.5 2.5
resulting in a mean and
standard deviation of
E(rHedged portfolio) (.5
16) (.3 2.5)
.2( 2.5) 8.25
Hedged portfolio [.5(16 - 8.25)2 .3(2.5 - 8.25)2 .2(-2.5 - 8.25)2]1/2 7.94
b. It is obvious that even under these
circumstances the hedging strategy dominates the risk-reducing strategy that
uses T-bills (which results in E(r)
7.75%,
9.45%). At the same time, the
standard deviation of the hedged position (7.94%)
is not as low as it was using
the original data.
c, d. Using rule 5 for portfolio variance, we
would find that
2
(.52 2Best) (.52
2Kane) [2 .5
.5 Cov(SugarKane, Best)]
(.52
18.92) (.52 8.722)
[2 .5 .5
(-90.5)] 63.06
which
implies that 7.94%, precisely the same
result that we obtained by an-