In: Statistics and Probability
A small building contractor has recently experienced two
successive years in which work opportunities exceeded the firm’s
capacity. The contractor must now make a decision on capacity for
next year. Estimated profits under each of the two possible states
of nature are as shown in the table below. Suppose after a certain
amount of discussion, the contractor is able to subjectively assess
the probabilities of low and high demand: P (low) = .3 and
P (high) = .7.
| NEXT YEAR'S DEMAND  | 
|||||
| Alternative | Low | High | |||
| Do nothing | $ | 50 | * | $ | 60 | 
| Expand | 20 | 80 | |||
| Subcontract | 40 | 70 | |||
* Profit in $ thousands.
a-1. Determine the expected profit of each
alternative. (Enter your answers in thousands. Omit the "$"
sign in your response.)
| Expected Profit | |
| Do Nothing | $ thousands | 
| Expand | $ thousands | 
| Subcontract | $ thousands | 
a-2. Which alternative is best?
Do nothing
Expand
Subcontract
c. Compute the expected value of perfect
information. (Enter your answers in thousands. Omit the "$"
sign in your response.)
EVPI      
    $  thousands
a-1) We are given the probability of low and high demand here
as:
P(low) = 0.3, and P(High) = 0.7
The expected profit for each alternative here is computed
as:
E(Do nothing) = 0.3*50 + 0.7*60 = 15 + 42 = $57
thousands
E(Expand) = 0.3*20 + 0.7*80 = $62 thousands
E(Subcontract) = 0.3*40 + 0.7*70 = 12 + 49 = $61
thousands
a-2) Based on the above expected profits for each alternative, we can clearly see here that the expected profit for Expand decision is $62 thousands. Therefore Expand is the best alternative here.
c) Expected value with perfect information here is computed
as:
= 0.3*Best expected value for Low demand + 0.7*Best expected value
for High demand
= 0.3*50 + 0.7*80
= 15 + 56
= $71 thousands
Therefore the expected value of perfect information is computed
here as:
= Expected value with perfect information - Expected value without
perfect information
= 71 - 62
= $9
Therefore $9 thousands is the required value here.