Problem 4: Recall the following portfolio allocation problem: an individual with initial wealth wo has to choose an allocation between a safe asset (with a zero rate of return) and a risky asset with a random rate of return = [−1,1], where E[6] > 0. If the individual invests x dollars in the risky asset, then final wealth is (wo-x) + x (1 + d) = w₁ +xd. The individual chooses x to maximize expected utility denoted by E[u(w₁ + xd)]. 1. Suppose the Bernoulli utility function is u(w) solute risk aversion is a constant. dwo ew. Show that ab- 2. Let x*(wo) denote the optimal amount of investment in the risky asset. Show that for the utility function of Part a., da = 0, i.e. the amount of investment in the risky asset is independent of initial wealth. Explain this result. 3. Now suppose that the utility function is u (w) = aw – ½bw², where a, b > 0. The parameters a and b are such that marginal utility of wealth is positive for all w. What can we say about in this case? Explain your result.

Microeconomic Theory
12th Edition
ISBN:9781337517942
Author:NICHOLSON
Publisher:NICHOLSON
Chapter7: Uncertainty
Section: Chapter Questions
Problem 7.7P
icon
Related questions
Question
Problem 4: Recall the following portfolio allocation problem: an individual
with initial wealth wo has to choose an allocation between a safe asset (with a
zero rate of return) and a risky asset with a random rate of return & € [−1, 1],
where E[8] > 0. If the individual invests & dollars in the risky asset, then final
wealth is (wo-x)+x(1+5) = w₁ +x6. The individual chooses to maximize
expected utility denoted by E[u(wo +xd)].
1. Suppose the Bernoulli utility function is u(w)
solute risk aversion is a constant.
= -e. Show that ab-
2. Let x* (wo) denote the optimal amount of investment in the risky asset.
Show that for the utility function of Part a., da = 0, i.e. the amount of
investment in the risky asset is independent of initial wealth. Explain this
result.
dwo
3. Now suppose that the utility function is u (w) = aw - bw², where a, b > 0.
The parameters a and b are such that marginal utility of wealth is positive
for all w. What can we say about in this case? Explain your result.
Transcribed Image Text:Problem 4: Recall the following portfolio allocation problem: an individual with initial wealth wo has to choose an allocation between a safe asset (with a zero rate of return) and a risky asset with a random rate of return & € [−1, 1], where E[8] > 0. If the individual invests & dollars in the risky asset, then final wealth is (wo-x)+x(1+5) = w₁ +x6. The individual chooses to maximize expected utility denoted by E[u(wo +xd)]. 1. Suppose the Bernoulli utility function is u(w) solute risk aversion is a constant. = -e. Show that ab- 2. Let x* (wo) denote the optimal amount of investment in the risky asset. Show that for the utility function of Part a., da = 0, i.e. the amount of investment in the risky asset is independent of initial wealth. Explain this result. dwo 3. Now suppose that the utility function is u (w) = aw - bw², where a, b > 0. The parameters a and b are such that marginal utility of wealth is positive for all w. What can we say about in this case? Explain your result.
Expert Solution
steps

Step by step

Solved in 5 steps with 5 images

Blurred answer
Knowledge Booster
Risk Aversion
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, economics and related others by exploring similar questions and additional content below.
Similar questions
  • SEE MORE QUESTIONS
Recommended textbooks for you
Microeconomic Theory
Microeconomic Theory
Economics
ISBN:
9781337517942
Author:
NICHOLSON
Publisher:
Cengage