session 2 - Olivier Brandouy

(Chap 6 BKM) .... 2-17. Olivier BRANDOUY, based on. INVESTMENTS | BODIE, KANE, MARCUS r f. = 7% σ rf. = 0%. E(r ... Example Using Chapter 6.4 Numbers ...
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SESSION 2 Risk Aversion and Capital Allocation to Risky Assets (Chap 6 BKM) Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS IAE de Paris, Master Finance, 2012-2013

2-2

Allocation to Risky Assets Investors will avoid risk unless there is a reward. The utility model gives the optimal allocation between a risky portfolio and a risk-free asset.

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-3

Risk and Risk Aversion Speculation – Taking considerable risk for a commensurate gain – Parties have heterogeneous expectations

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-4

Risk and Risk Aversion Gamble – Bet or wager on an uncertain outcome for enjoyment – Parties assign the same probabilities to the possible outcomes

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-5

Risk Aversion and Utility Values Investors are willing to consider: – risk-free assets – speculative positions with positive risk premiums

Portfolio attractiveness increases with expected return and decreases with risk. What happens when return increases with risk? Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-6

Table 6.1 Available Risky Portfolios (Risk-free Rate = 5%)

Each portfolio receives a utility score to assess the investor’s risk/return trade off Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-7

Utility Function U = utility E ( r ) = expected return on the asset or portfolio A = coefficient of risk aversion σ2 = variance of returns ½ = a scaling factor

1 2 U = E (r)− Aσ 2

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

Table 6.2 Utility Scores of Alternative Portfolios for Investors with Varying Degree of Risk Aversion

2-8

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-9

Mean-Variance (M-V) Criterion Portfolio A dominates portfolio B if:

E ( rA ) ≥ E ( rB ) And

σA ≤σB Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-10

Estimating Risk Aversion Use questionnaires Observe individuals’ decisions when confronted with risk Observe how much people are willing to pay to avoid risk Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-11

Capital Allocation Across Risky and Risk-Free Portfolios Asset Allocation: Is a very important part of portfolio construction. Refers to the choice among broad asset classes.

Controlling Risk:

Simplest way: Manipulate the fraction of the portfolio invested in risk-free assets versus the portion invested in the risky assets

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-12

Basic Asset Allocation Total Market Value Risk-free money market fund Equities Bonds

$113,400 WE = = 0.54 $210,000 Total risk assets

$300,000 $90,000 $113,400 $96,600

$96,600 WB = = 0.46 $210,00 $210,000 Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-13

Basic Asset Allocation Let y = weight of the risky portfolio, P, in the complete portfolio; (1-y) = weight of risk-free assets: $210,000 y= = 0.7 $300,000

$113,400 E: = .378 $300,000

$90,000 1− y = = 0.3 $300,000

$96,600 B: = .322 $300,000

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-14

The Risk-Free Asset Only the government can issue defaultfree bonds. – Risk-free in real terms only if price indexed and maturity equal to investor’s holding period.

T-bills viewed as “the” risk-free asset Money market funds also considered risk-free in practice Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-15

Figure 6.3 Spread Between 3-Month CD and T-bill Rates

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-16

Portfolios of One Risky Asset and a Risk-Free Asset It’s possible to create a complete portfolio by splitting investment funds between safe and risky assets. – Let y=portion allocated to the risky portfolio, P – (1-y)=portion to be invested in risk-free asset, F.

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-17

Example Using Chapter 6.4 Numbers

rf = 7% E(rp) = 15% y = % in p

σ rf = 0% σ p = 22% (1-y) = % in rf

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-18

Example (Ctd.) The expected return on the complete portfolio is the risk-free rate plus the weight of P times the risk premium of P

E (r c )=r f + y [E (r p )−r f ]

E ( rc ) = 7 + y(15− 7) Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-19

Example (Ctd.) The risk of the complete portfolio is the weight of P times the risk of P:

σ C = yσ P = 22y

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-20

Example (Ctd.) Rearrange and substitute y=σC/σP:

σC 8 [ E ( rC ) = rf + E ( rP ) − rf ] = 7+ σ C σP 22 Slope=

E ( r P ) −r f σP

8 = 22

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

Figure 6.4 The Investment Opportunity Set

2-21

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-22

Capital Allocation Line with Leverage Lend at rf=7% and borrow at rf=9% – Lending range slope = 8/22 = 0.36 – Borrowing range slope = 6/22 = 0.27 CAL kinks at P

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-23

Figure 6.5 The Opportunity Set with Differential Borrowing and Lending Rates

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-24

Risk Tolerance and Asset Allocation The investor must choose one optimal portfolio, C, from the set of feasible choices – Expected return of the complete portfolio: E (r c )=r f + y [E (r p )−r f ] – Variance:

σ = yσ 2 C

2

2 P

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-25

Table 6.4 Utility Levels for Various Positions in Risky Assets (y) for an Investor with Risk Aversion A = 4

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-26

Figure 6.6 Utility as a Function of Allocation to the Risky Asset, y

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-27

Table 6.5 Spreadsheet Calculations of Indifference Curves

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-28

Figure 6.7 Indifference Curves for U = .05 and U = .09 with A = 2 and A = 4

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-29

Figure 6.8 Finding the Optimal Complete Portfolio Using Indifference Curves

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-30

Table 6.6 Expected Returns on Four Indifference Curves and the CAL

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

Passive Strategies: The Capital Market Line

2-31

The passive strategy avoids any direct or indirect security analysis Supply and demand forces may make such a strategy a reasonable choice for many investors

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

Passive Strategies: The Capital Market Line

2-32

A natural candidate for a passively held risky asset would be a well-diversified portfolio of common stocks such as the S&P 500. The capital market line (CML) is the capital allocation line formed from 1-month T-bills and a broad index of common stocks (e.g. the S&P 500).

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-33

Passive Strategies: The Capital Market Line The CML is given by a strategy that involves investment in two passive portfolios: 1. virtually risk-free short-term T-bills (or a money market fund) 2. a fund of common stocks that mimics a broad market index. Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-34

Passive Strategies: The Capital Market Line From 1926 to 2009, the passive risky portfolio offered an average risk premium of 7.9% with a standard deviation of 20.8%, resulting in a reward-to-volatility ratio of .38.

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

SESSION 2 Risk Aversion and Capital Allocation to Risky Assets (Chap 6 BKM) Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS IAE de Paris, Master Finance, 2012-2013

2-2

Allocation to Risky Assets Investors will avoid risk unless there is a reward. The utility model gives the optimal allocation between a risky portfolio and a risk-free asset.

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-3

Risk and Risk Aversion Speculation – Taking considerable risk for a commensurate gain – Parties have heterogeneous expectations

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-4

Risk and Risk Aversion Gamble – Bet or wager on an uncertain outcome for enjoyment – Parties assign the same probabilities to the possible outcomes

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-5

Risk Aversion and Utility Values Investors are willing to consider: – risk-free assets – speculative positions with positive risk premiums

Portfolio attractiveness increases with expected return and decreases with risk. What happens when return increases with risk? Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-6

Table 6.1 Available Risky Portfolios (Risk-free Rate = 5%)

Each portfolio receives a utility score to assess the investor’s risk/return trade off Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-7

Utility Function U = utility E ( r ) = expected return on the asset or portfolio A = coefficient of risk aversion σ2 = variance of returns ½ = a scaling factor

U = E (r)−

1 2 Aσ 2

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

Table 6.2 Utility Scores of Alternative Portfolios for Investors with Varying Degree of Risk Aversion

2-8

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-9

Mean-Variance (M-V) Criterion Portfolio A dominates portfolio B if:

E ( rA ) ≥ E ( rB ) And

σA ≤σB Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-10

Estimating Risk Aversion Use questionnaires Observe individuals’ decisions when confronted with risk Observe how much people are willing to pay to avoid risk Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-11

Capital Allocation Across Risky and Risk-Free Portfolios Asset Allocation: Is a very important part of portfolio construction. Refers to the choice among broad asset classes.

Controlling Risk:

Simplest way: Manipulate the fraction of the portfolio invested in risk-free assets versus the portion invested in the risky assets

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-12

Basic Asset Allocation Total Market Value Risk-free money market fund Equities Bonds

$113,400 WE = = 0.54 $210,000 Total risk assets

$300,000 $90,000 $113,400 $96,600

WB =

$96,600 = 0.46 $210,00

$210,000 Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-13

Basic Asset Allocation Let y = weight of the risky portfolio, P, in the complete portfolio; (1-y) = weight of risk-free assets: y=

$210,000 = 0.7 $300,000

$113,400 E: = .378 $300,000

1− y =

$90,000 = 0.3 $300,000

$96,600 B: = .322 $300,000

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-14

The Risk-Free Asset Only the government can issue defaultfree bonds. – Risk-free in real terms only if price indexed and maturity equal to investor’s holding period.

T-bills viewed as “the” risk-free asset Money market funds also considered risk-free in practice Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-15

Figure 6.3 Spread Between 3-Month CD and T-bill Rates

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-16

Portfolios of One Risky Asset and a Risk-Free Asset It’s possible to create a complete portfolio by splitting investment funds between safe and risky assets. – Let y=portion allocated to the risky portfolio, P – (1-y)=portion to be invested in risk-free asset, F.

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-17

Example Using Chapter 6.4 Numbers

rf = 7% E(rp) = 15% y = % in p

σ rf = 0% σ p = 22% (1-y) = % in rf

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-18

Example (Ctd.) The expected return on the complete portfolio is the risk-free rate plus the weight of P times the risk premium of P

E (r c )=r f + y [E (r p )−r f ]

E ( rc ) = 7 + y(15− 7) Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-19

Example (Ctd.) The risk of the complete portfolio is the weight of P times the risk of P:

σ C = yσ P = 22y

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-20

Example (Ctd.) Rearrange and substitute y=σC/σP: E ( rC ) = rf +

σC 8 [ E ( rP ) − rf ] = 7+ σ C σP 22

Slope=

E ( r P ) −r f σP

=

8 22

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

Figure 6.4 The Investment Opportunity Set

2-21

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-22

Capital Allocation Line with Leverage Lend at rf=7% and borrow at rf=9% – Lending range slope = 8/22 = 0.36 – Borrowing range slope = 6/22 = 0.27 CAL kinks at P

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-23

Figure 6.5 The Opportunity Set with Differential Borrowing and Lending Rates

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-24

Risk Tolerance and Asset Allocation The investor must choose one optimal portfolio, C, from the set of feasible choices – Expected return of the complete portfolio: E (r c )=r f + y [E (r p )−r f ] – Variance:

σ C2 = y2σ P2

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-25

Table 6.4 Utility Levels for Various Positions in Risky Assets (y) for an Investor with Risk Aversion A = 4

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-26

Figure 6.6 Utility as a Function of Allocation to the Risky Asset, y

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-27

Table 6.5 Spreadsheet Calculations of Indifference Curves

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-28

Figure 6.7 Indifference Curves for U = .05 and U = .09 with A = 2 and A = 4

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-29

Figure 6.8 Finding the Optimal Complete Portfolio Using Indifference Curves

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-30

Table 6.6 Expected Returns on Four Indifference Curves and the CAL

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

Passive Strategies: The Capital Market Line

2-31

The passive strategy avoids any direct or indirect security analysis Supply and demand forces may make such a strategy a reasonable choice for many investors

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-32

Passive Strategies: The Capital Market Line A natural candidate for a passively held risky asset would be a well-diversified portfolio of common stocks such as the S&P 500. The capital market line (CML) is the capital allocation line formed from 1-month T-bills and a broad index of common stocks (e.g. the S&P 500).

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-33

Passive Strategies: The Capital Market Line The CML is given by a strategy that involves investment in two passive portfolios: 1. virtually risk-free short-term T-bills (or a money market fund) 2. a fund of common stocks that mimics a broad market index. Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS

2-34

Passive Strategies: The Capital Market Line From 1926 to 2009, the passive risky portfolio offered an average risk premium of 7.9% with a standard deviation of 20.8%, resulting in a reward-to-volatility ratio of .38.

Olivier BRANDOUY, based on INVESTMENTS | BODIE, KANE, MARCUS