Principles of Finance ACST603
Tutorial 8, Week 8 Statistical concepts and risk
Homework questions.
A share was bought for $20 (at t=0) and paid its annual dividend of $3 one year later (at t=1). Just after the dividend was paid, the share price was $16 (at t=1). What was the total return, capital return and income return? Calculate your answers as effective annual rates.
The choices are given in the same order: ## r_\text{total},r_\text{capital},r_\text{income} ##.
Which of the following statements about an asset’s standard deviation of returns is NOT correct? All other things remaining equal, the higher the asset’s standard deviation of returns:
Stock A and B's returns have a correlation of 0.3. Which statement is NOT correct?
The following table shows a sample of historical total returns of shares in two different companies A and B.
Stock Returns | ||
Total effective annual returns | ||
Year | ##r_A## | ##r_B## |
2007 | 0.2 | 0.4 |
2008 | 0.04 | -0.2 |
2009 | -0.1 | -0.3 |
2010 | 0.18 | 0.5 |
What is the historical sample covariance (##\hat{\sigma}_{A,B}##) and correlation (##\rho_{A,B}##) of stock A and B's total effective annual returns?
Portfolio Details | ||||||
Stock | Expected return |
Standard deviation |
Correlation | Dollars invested |
||
A | 0.1 | 0.4 | 0.5 | 60 | ||
B | 0.2 | 0.6 | 140 | |||
What is the expected return of the above portfolio?
All things remaining equal, the variance of a portfolio of two positively-weighted stocks rises as:
Diversification in a portfolio of two assets works best when the correlation between their returns is:
Portfolio Details | ||||||
Stock | Expected return |
Standard deviation |
Covariance ##(\sigma_{A,B})## | Beta | Dollars invested |
|
A | 0.2 | 0.4 | 0.12 | 0.5 | 40 | |
B | 0.3 | 0.8 | 1.5 | 80 | ||
What is the standard deviation (not variance) of the above portfolio? Note that the stocks' covariance is given, not correlation.
Question 558 portfolio weights, portfolio return, short selling
An investor wants to make a portfolio of two stocks A and B with a target expected portfolio return of 16% pa.
- Stock A has an expected return of 8% pa.
- Stock B has an expected return of 12% pa.
What portfolio weights should the investor have in stocks A and B respectively?
The standard deviation and variance of a stock's annual returns are calculated over a number of years. The units of the returns are percent per annum ##(\% pa)##.
What are the units of the standard deviation ##(\sigma)## and variance ##(\sigma^2)## of returns respectively?
Hint: Visit Wikipedia to understand the difference between percentage points ##(\text{pp})## and percent ##(\%)##.
A stock's returns are normally distributed with a mean of 10% pa and a standard deviation of 20 percentage points pa. What is the 90% confidence interval of returns over the next year? Note that the Z-statistic corresponding to a one-tail:
- 90% normal probability density function is 1.282.
- 95% normal probability density function is 1.645.
- 97.5% normal probability density function is 1.960.
The 90% confidence interval of annual returns is between:
A stock's returns are normally distributed with a mean of 10% pa and a standard deviation of 20 percentage points pa. What is the 95% confidence interval of returns over the next year? Note that the Z-statistic corresponding to a one-tail:
- 90% normal probability density function is 1.282.
- 95% normal probability density function is 1.645.
- 97.5% normal probability density function is 1.960.
The 95% confidence interval of annual returns is between:
A stock has an expected return of 10% pa and you're 90% sure that over the next year, the return will be between -15% and 35%. The stock's returns are normally distributed. Note that the Z-statistic corresponding to a one-tail:
- 90% normal probability density function is 1.282.
- 95% normal probability density function is 1.645.
- 97.5% normal probability density function is 1.960.
What is the stock’s standard deviation of returns in percentage points per annum (pp pa)?
Question 282 expected and historical returns, income and capital returns
You're the boss of an investment bank's equities research team. Your five analysts are each trying to find the expected total return over the next year of shares in a mining company. The mining firm:
- Is regarded as a mature company since it's quite stable in size and was floated around 30 years ago. It is not a high-growth company;
- Share price is very sensitive to changes in the price of the market portfolio, economic growth, the exchange rate and commodities prices. Due to this, its standard deviation of total returns is much higher than that of the market index;
- Experienced tough times in the last 10 years due to unexpected falls in commodity prices.
- Shares are traded in an active liquid market.
- The analysts' source data is correct and true, but their inferences might be wrong;
- All returns and yields are given as effective annual nominal rates.
Question 559 variance, standard deviation, covariance, correlation
Which of the following statements about standard statistical mathematics notation is NOT correct?
What is the covariance of a variable X with itself?
The cov(X, X) or ##\sigma_{X,X}## equals:
What is the correlation of a variable X with itself?
The corr(X, X) or ##\rho_{X,X}## equals:
What is the covariance of a variable X with a constant C?
The cov(X, C) or ##\sigma_{X,C}## equals:
What is the correlation of a variable X with a constant C?
The corr(X, C) or ##\rho_{X,C}## equals: