In: Statistics and Probability
You have $390,000 invested in a well-diversified portfolio. You inherit a house that is presently worth $230,000. Consider the summary measures in the following table:
Investment | Expected Return | Standard Deviation | ||
Old portfolio | 5 | % | 13 | % |
House | 15 | % | 18 | % |
The correlation coefficient between your portfolio and the house is
0.43.
a. What is the expected return and the standard deviation for your portfolio comprising your old portfolio and the house? (Do not round intermediate calculations. Round your final answers to 2 decimal places.)
Expected return | % |
Standard deviation | % |
b. Suppose you decide to sell the house and use the proceeds of $230,000 to buy risk-free T-bills that promise a 10% rate of return. Calculate the expected return and the standard deviation for the resulting portfolio. [Hint: Note that the correlation coefficient between any asset and the risk-free T-bills is zero.] (Do not round intermediate calculations. Round your final answers to 2 decimal places.)
Expected return | % |
Standard deviation | % |
Expected Return of a portfolio is given by,
Where
Here is the weight of the ith asset
And ri is the return (expected) from the ith asset
Assets |
Investment ($) |
Weight (Wi) |
Expected Return(%) (ri) |
Standard Deviation(%) (si) |
Old Portfolio |
390000 |
0.629032258 |
5 |
13 |
House |
230000 |
0.370967742 |
15 |
18 |
Total |
620000 |
1 |
So, expected return is= 0.629032258*5 + 0.370967742*15
=8.709677419
≈ 8.71%
Standard Deviation =
Where r is the correlation coefficient between the 2 assets.
Here, S.D = 12.58640563 (Calculated using Excel with the help of the above formula)
Expected Return (%) |
8.709677419 |
Standard deviation(%) |
12.58640563 |
He sold the house and bought a Risk-free-T bills with 10% return so, the portfolio becomes:
Assets |
Investment ($) |
Weight(W) |
Expected Return(%) |
Standard Deviation(%) |
Old Portfolio |
390000 |
0.629032258 |
5 |
13 |
Risk-free-T bills |
230000 |
0.370967742 |
10 |
18 |
Total |
620000 |
1 |
So, expected return for the new portfolio is =6.85%
(since the Correlation coefficient is 0, So the formula for S.D becomes as follows:
Standard Deviation = ( since, r=0)
Standard deviation = 10.56 %
Expected Return (%) |
6.85483871 |
Standard deviation(%) |
10.55737262 |