FrankSun · 2019年12月21日
问题如下：
Kam Bergeron is a risk-averse investor. He will apply utility theory to choose the investment portfolio. The table shows the expected return and expected standard deviation of several investments, assuming the measure of risk aversion is 3, he is most likely to invest:
选项：
A.2
B.3
C.4
解释：
A is correct.
Investment 2 provides the highest utility value (0.1979) for Kam Bergeron who has a measure of risk aversion equal to 3.
请老师解答一下他们都是怎么算的
星星_品职助教 · 2019年12月23日
同学你好，
这道题是根据utility function“U=E(r)-1/2Aσ2”来计算的，例如investment 1，代入E(r)=0.19，σ=0.03，A=3，可以得到utility,0.1887.以此类推。
按照目前原版书的出题风格，正常utility function在计算题里都是给出的。所以不用担心，也可以把这个公式记忆一下，加油。
Hugo(Xie Lanzhi) · 2020年05月02日
U=E(r)-1/2Aσ^2 代入得到：U=0.19-1/2*3*0.03^2=0.19-1/0.0054=0,19-185.19=-184.995, 看了眼原版书才知道原来是乘以0.5，如果是不知道原来公示的同学很容易像我这么算我觉得，建议修改一下公示的呈现方式，如果呈现不方便的话，要不就改为乘以0.5好了。。。
NO.PZ2018070201000057问题如下KBergeron is a risk-averse investor. He will apply utility theory to choose the investment portfolio. The table shows the expectereturn anexpectestanrviation of severinvestments, assuming the measure of risk aversion is 3, U=E(r)-1/2Aσ2, he is most likely to invest:A.2B.3C.4A is correct.Investment 2 provis the highest utility value (0.1979) for KBergeron who ha measure of risk aversion equto 3.即不同类型的投资者都是选最大的U？
3 4 A is correct. Investment 2 provis the highest utility value (0.1979) for KBergeron who ha measure of risk aversion equto 3. 这人是风险厌恶型 所以应该选效用最小的呀。所以是4。之前有一题选风险喜好型才选效用最大的
investment 3的utility 算错了，应该是0.1900
