In: Statistics and Probability
Problem 13-29 (Algorithmic)
Three decision makers have assessed utilities for the following decision problem (payoff in dollars):
State of Nature |
|||
Decision Alternative |
S1 |
S2 |
S3 |
d1 |
10 |
40 |
-30 |
d2 |
90 |
110 |
-80 |
The indifference probabilities are as follows:
Indifference Probability (p) |
|||
Payoff |
Decision maker A |
Decision maker B |
Decision maker C |
110 |
1.00 |
1.00 |
1.00 |
90 |
0.95 |
0.80 |
0.85 |
40 |
0.85 |
0.70 |
0.75 |
10 |
0.75 |
0.55 |
0.60 |
-30 |
0.60 |
0.25 |
0.50 |
-80 |
0.00 |
0.00 |
0.00 |
Find a recommended decision for each of the three decision makers, if P(s1) = 0.25, P(s2) = 0.60, and P(s3) = 0.15. (Note: For the same decision problem, different utilities can lead to different decisions.) If required, round your answers to two decimal places.
Decision maker A |
EU(d1) = |
EU(d2) = |
Recommended decision: |
Decision maker B |
EU(d1) = |
EU(d2) = |
Recommended decision: |
Decision maker C |
EU(d1) = |
EU(d2) = |
Recommended decision: |
Ans. Expected value / utility here is a weighted average of the payoffs for a decision alternative.
EU (something) = Probablities * payoff values
In the second indifference probability table payoffs are the same as the first table & given by the combination of payoff between s1,s2,s3 and given ascendingly. The payoff of decision 1 in first table which exactly be given in the second table & corresponding probabilities , those will be using to calculate the EU(d1) for decision maker A,B,C and same process will be following to calculate the EU(d2) for decision maker A,B,C.
Decision maker A |
EU(d1) = 23.5 |
EU(d2) = 195.5 EU(d2) - EU(d1) = 172 |
Recommended decision: d2 |
Decision maker B |
EU(d1) = 24 |
EU(d2) = 182 EU(d2) - EU(d1) = 182 - 24 = 158 |
Recommended decision: d2 |
Decision maker C |
EU(d1) = 34.5 |
EU(d2) = 186.5 EU(d2) - EU(d1) = 186.5 - 34.5 = 152 |
Recommended decision: d2 Now expected utility of EU(d1) & EU(d2) across state of nature : Since P(s1) = 0.25 P(s2) = 0.60 P(s3) = 0.15 So, EU(d1) = 10*0.25 + 40*0.60 - 30*0.15 = 22 EU(d2) = 90*0.25 + 110*0.60 - 80*0.15 = 76.5 Now EU(d2) - EU(d1) = 54.5 So if EU(d2) - EU(d1) <=> 54.5 , for three decision makers then decision makers will decide d1, indifferent between two , d2 accordingly. |