This document defines key concepts related to risk and return in finance. It discusses how return is calculated based on income and price changes. It also defines risk as the variability of actual returns compared to expected returns. The document introduces the capital asset pricing model (CAPM), which relates a security's expected return to its systematic risk (beta). It describes how beta measures the sensitivity of a stock's returns to market returns. The CAPM holds that a security's expected return is determined by the risk-free rate and a risk premium based on the security's beta. The document provides examples of how to calculate portfolio expected returns and standard deviations, as well as how to determine the required rate of return and intrinsic value of individual stocks using CAP
2. Defining Return
Income receivedIncome received on an investment plus any
change in market pricechange in market price, usually expressed
as a percent of the beginning market pricebeginning market price
of the investment.
DDtt + (PPtt - P- Pt-1t-1 )
PPt-1t-1
R =
2
3. Return Example
The stock price for Stock A was $10$10 per share
1 year ago. The stock is currently trading at
$9.50$9.50 per share and shareholders just
received a $1 dividend$1 dividend. What return was
earned over the past year?
3
4. Return Example
The stock price for Stock A was $10$10 per share
1 year ago. The stock is currently trading at
$9.50$9.50 per share and shareholders just
received a $1 dividend$1 dividend. What return was
earned over the past year?
$1.00$1.00 + ($9.50$9.50 - $10.00$10.00 )
$10.00$10.00RR = = 5%5%
4
5. Defining Risk
What rate of return do you expect on yourWhat rate of return do you expect on your
investment (savings) this year?investment (savings) this year?
What rate will you actually earn?What rate will you actually earn?
Does it matter if it is a bank CD or a share ofDoes it matter if it is a bank CD or a share of
stock?stock?
The variability of returns from thoseThe variability of returns from those
that are expected.that are expected.
5
6. Determining Expected
Return
R = Σ ( Ri )( Pi )
R is the expected return for the asset,
Ri is the return for the ith
possibility,
Pi is the probability of that return occurring,
n is the total number of possibilities.
n
i=1
6
7. How to Determine the
Expected Return and
Standard Deviation
Stock BW
Ri Pi (Ri)(Pi)
-.15 .10 -.015
-.03 .20 -.006
.09 .40 .036
.21 .20 .042
.33 .10 .033
Sum 1.00 .090.090
The
expected
return, R,
for Stock
BW is .09
or 9%
7
8. Determining Standard
Deviation (Risk
Measure)
σσ = Σ ( Ri - R )2
( Pi )
Standard DeviationStandard Deviation, σσ, is a statistical measure
of the variability of a distribution around its
mean.
It is the square root of variance.
n
i=1
8
9. How to Determine the
Expected Return and
Standard Deviation
Stock BW
Ri Pi (Ri)(Pi) (Ri - R )2
(Pi)
-.15 .10 -.015 .00576
-.03 .20 -.006 .00288
.09 .40 .036 .00000
.21 .20 .042 .00288
.33 .10 .033 .00576
Sum 1.00 .090.090 .01728.01728
9
11. Coefficient of
Variation
The ratio of the standard deviationstandard deviation of a
distribution to the meanmean of that distribution.
It is a measure of RELATIVERELATIVE risk.
CV = σσ / RR
CV of BW = .1315.1315 / .09.09 = 1.46
11
12. Certainty EquivalentCertainty Equivalent (CECE) is the amount of
cash someone would require with certainty
at a point in time to make the individual
indifferent between that certain amount and
an amount expected to be received with risk
at the same point in time.
Risk Attitudes
12
13. Certainty equivalent > Expected value
Risk PreferenceRisk Preference
Certainty equivalent = Expected value
Risk IndifferenceRisk Indifference
Certainty equivalent < Expected value
Risk AversionRisk Aversion
Most individuals are Risk AverseRisk Averse.
Risk Attitudes
13
14. Risk Attitude Example
You have the choice between (1) a guaranteed
dollar reward or (2) a coin-flip gamble of
$100,000 (50% chance) or $0 (50% chance).
The expected value of the gamble is $50,000.
– Mary requires a guaranteed $25,000, or more, to call
off the gamble.
– Raleigh is just as happy to take $50,000 or take the
risky gamble.
– Shannon requires at least $52,000 to call off the
gamble.
14
15. What are the Risk Attitude tendencies of each?What are the Risk Attitude tendencies of each?
Risk Attitude Example
Mary shows “risk aversion”“risk aversion” because her “certainty
equivalent” < the expected value of the gamble..
Raleigh exhibits “risk indifference”“risk indifference” because her
“certainty equivalent” equals the expected value of
the gamble..
Shannon reveals a “risk preference”“risk preference” because her
“certainty equivalent” > the expected value of the
gamble..
15
16. RP = Σ ( Wj )( Rj )
RP is the expected return for the portfolio,
Wj is the weight (investment proportion) for
the jth
asset in the portfolio,
Rj is the expected return of the jth
asset,
m is the total number of assets in the portfolio.
Determining Portfolio
Expected Return
m
j=1
16
17. Determining Portfolio
Standard Deviation
m
j=1
m
k=1
σσPP = Σ Σ Wj Wk σjk
Wj is the weight (investment proportion) for
the jth
asset in the portfolio,
Wk is the weight (investment proportion) for the
kth
asset in the portfolio,
σjk is the covariance between returns for the jth
and kth
assets in the portfolio. 17
18. Standard Deviation of
Two Asset Portfolio
The before mentioned formula can be expressed as
following for two asset portfolio;
σσPP==√W√Wjj
22
σσjj
22
++WWkk
22
σσkk
22
+2W+2WjjWWkkσσjkjk
wherewhere σσjk isjk is covariancecovariance
or,or,
σσPP==√W√Wjj
22
σσjj
22
++WWkk
22
σσkk
22
+2W+2WjjWWkkrrjkjkσσjjσσkk
wherewhererrjkjk is correlation coefficientis correlation coefficient
18
19. What is Covariance?
σσ jk = σ j σ k rr jk
σj is the standard deviation of the jth
asset in
the portfolio,
σkis the standard deviation of the kth
asset in
the portfolio,
rjk is the correlation coefficient between the jth
and kth
assets in the portfolio.
19
20. Correlation Coefficient
A standardized statistical measure of the
linear relationship between two variables.
Its range is from -1.0-1.0 (perfect negative
correlation), through 00 (no correlation), to
+1.0+1.0 (perfect positive correlation).
20
21. You are creating a portfolio of Stock DStock D and Stock BWStock BW
(from earlier). You are investing $2,000$2,000 in Stock BWStock BW
and $3,000$3,000 in Stock DStock D. Remember that the expected
return and standard deviation of Stock BWStock BW is 9%9% and
13.15%13.15% respectively. The expected return and
standard deviation of Stock DStock D is 8%8% and 10.65%10.65%
respectively. The correlation coefficientcorrelation coefficient between BW
and D is 0.750.75.
What is the expected return and standardWhat is the expected return and standard
deviation of the portfolio?deviation of the portfolio?
Portfolio Risk and Expected
Return Example
21
23. Determining Portfolio
Standard Deviation
σP = .0028 + (2)(.0025) + .0041
σP = SQRT(.0119)
σP = .1091 or 10.91%
A weighted average of the individual standard
deviations is INCORRECT.
23
24. Determining Portfolio
Standard Deviation
The WRONG way to calculate is a
weighted average like:
σP = .4 (13.15%) + .6(10.65%)
σP = 5.26 + 6.39 = 11.65%
10.91% = 11.65%
This is INCORRECT.
24
25. Stock C Stock D Portfolio
ReturnReturn 9.00% 8.00% 8.64%
Stand.Stand.
Dev.Dev. 13.15% 10.65% 10.91%
CVCV 1.46 1.33 1.26
The portfolio has the LOWEST coefficient of
variation due to diversification.
Summary of the Portfolio
Return and Risk
Calculation
25
26. Combining securities that are not perfectly,
positively correlated reduces risk.
Diversification and the
Correlation Coefficient
INVESTMENTRETURN
TIME TIMETIME
SECURITY ESECURITY E SECURITY FSECURITY F
CombinationCombination
E and FE and F
26
27. Systematic RiskSystematic Risk is the variability of return on
stocks or portfolios associated with changes in
return on the market as a whole.
Unsystematic RiskUnsystematic Risk is the variability of return on
stocks or portfolios not explained by general
market movements. It is avoidable through
diversification.
Total Risk = Systematic
Risk + Unsystematic
Risk
Total RiskTotal Risk = SystematicSystematic RiskRisk +
UnsystematicUnsystematic RiskRisk
27
28. Total Risk =
Systematic Risk +
Unsystematic Risk
TotalTotal
RiskRisk
Unsystematic riskUnsystematic risk
Systematic riskSystematic risk
STDDEVOFPORTFOLIORETURN
NUMBER OF SECURITIES IN THE PORTFOLIO
Factors such as changes in nation’s
economy, tax reform by the Congress,
or a change in the world situation.
28
29. Total Risk =
Systematic Risk +
Unsystematic Risk
TotalTotal
RiskRisk
Unsystematic riskUnsystematic risk
Systematic riskSystematic risk
STDDEVOFPORTFOLIORETURN
NUMBER OF SECURITIES IN THE PORTFOLIO
Factors unique to a particular company
or industry. For example, the death of a
key executive or loss of a governmental
defense contract.
29
30. CAPM is a model that describes the
relationship between risk and expected
(required) return; in this model, a security’s
expected (required) return is the risk-free raterisk-free rate
plus a premiuma premium based on the systematic risksystematic risk
of the security.
Capital Asset
Pricing Model (CAPM)
30
31. 1. Capital markets are efficient.
2. Homogeneous investor expectations
over a given period.
3. Risk-freeRisk-free asset return is certain
(use short- to intermediate-term
Treasuries as a proxy).
4. Market portfolio contains only
systematic risksystematic risk (use S&P 500 Index
or similar as a proxy).
CAPM Assumptions
31
32. An index of systematic risksystematic risk.
It measures the sensitivity of a stock’s
returns to changes in returns on the market
portfolio.
The betabeta for a portfolio is simply a weighted
average of the individual stock betas in the
portfolio.
What is Beta?
32
33. RRjj is the required rate of return for stock j,
RRff is the risk-free rate of return,
ββjj is the beta of stock j (measures systematic
risk of stock j),
RRMM is the expected return for the market
portfolio.
Security Market Line
RRjj = RRff + ββj(RRMM - RRff)
33
35. Lisa Miller at Basket Wonders is attempting to
determine the rate of return required by their
stock investors. Lisa is using a 6% R6% Rff and a
long-term market expected rate of returnmarket expected rate of return of
10%10%. A stock analyst following the firm has
calculated that the firm betabeta is 1.21.2. What is
the required rate of returnrequired rate of return on the stock of
Basket Wonders?
Determination of the
Required Rate of Return
35
36. RRBWBW = RRff + ββj(RRMM - RRff)
RRBWBW = 6%6% + 1.21.2(10%10% - 6%6%)
RRBWBW = 10.8%10.8%
The required rate of return exceeds the
market rate of return as BW’s beta exceeds
the market beta (1.0).
BWs Required Rate of
Return
36
37. Lisa Miller at BW is also attempting to determine
the intrinsic valueintrinsic value of the stock. She is using the
constant growth model. Lisa estimates that the
dividend next perioddividend next period will be $0.50$0.50 and that BW
will growgrow at a constant rate of 5.8%5.8%. The stock
is currently selling for $15.
What is the intrinsic valueintrinsic value of the stock? Is
the stock overover or underpricedunderpriced?
Determination of the
Intrinsic Value of BW
37
38. The stock is OVERVALUED as the
market price ($15) exceeds the
intrinsic valueintrinsic value ($10$10).
Determination of the
Intrinsic Value of BW
$0.50$0.50
10.8%10.8% - 5.8%5.8%
IntrinsicIntrinsic
ValueValue
=
= $10$10
38
39. Security Market Line
Systematic Risk (Beta)
RRff
RequiredReturnRequiredReturn
Direction of
Movement
Direction of
Movement
Stock YStock Y (Overpriced)
Stock X (Underpriced)
39