3QA3/2DA3
Management Science for
Lecture 06
C01: July 7, 2021
C02: July 8, 2021
Instructors:
Seyyed Hossein Alavi Zdravko Dimitrov
Decision Analysis
Decision Analysis
3
We live in a world surrounded by uncertainties and risks.
We have to make a decision, without knowing for sure which
events will occur in the future.
We’d better consider all decision alternatives before we make a
decision.
Decision analysis is an analytic and systematic approach to the study
of decision making.
Steps of Decision Making
4
1. Clearly define the problem
2. List ALL possible alternatives
3. Identify all possible outcomes for each alternative
4. Identify the payoff for each alternative and outcome combination
5. Use a decision modeling technique to choose an alternative
Types of Decision Making
5
Under Certainty
We know the consequence of all alternatives.
Under Uncertainty
We do not know the probability of each outcome.
Under Risk
We know the probability of each outcome.
Decision Making Under Uncertainty
6
The manager can list the possible future outcomes but cannot
estimate the probability that a specific outcome will occur.
Five different decision-making criteria can be used to make a decision:
1. Maximax
2. Maximin
3. Realism
4. Equally likely
5. Minimax regret
Drilling Example
7
A drilling company has a land. The manager would like to consider
two alternatives:
1. Drill the land for oil
2. Sell the land
The possible outcomes (state of nature) are:
1. Oil
2. Dry
The payoffs are:
1. If the company finds oil: profit of $700
2. If the company cannot find oil: cost of $100
3. If the company sells the land: profit of $90
Drilling Example
8
Payoff Table:
Alternatives
Outcomes (States of nature)
Oil Dry
Drill for oil $700 -$100
Sell the land $90 $90
1-Maximax
9
For each alternative, find the maximum payoff over all possible outcomes. Next,
find the maximum of them. Choose the alternative whose maximum payoff gives
this maximum.
It is choosing the alternative with the best payoff, if the best outcome happens
(optimistic!)
Alternatives
Outcomes
(States of nature) Max
Oil Dry
Drill for oil $700 -$100 700
Sell the land $90 $90 90
Max
2-Maximin
10
For each alternative, find the minimum payoff over all possible outcomes. Next,
find the maximum of them. Chose the alternative whose minimum payoff gives
this maximum.
It is choosing the alternative with best payoff, if the worst outcome happens
(pessimistic!)
Alternatives
Outcomes
(States of nature) Min
Oil Dry
Drill for oil $700 -$100 -100
Sell the land $90 $90 90
Max
3-Criterion of Realism
11
Decision makers should not be optimists or pessimists. They should be realistic.
Define Coefficient of Realism: 0 ≤ ? ≤ 1
? = 1 means the decision maker is totally optimistic.(Maximax)
? = 0 means the decision maker is totally pessimistic.(Maximin)
Calculate the realism payoff for each alternative and select the alternative with the
highest realism payoff.
Realism Payoff = ? × ??? ?????? + 1 − ? × ??? ??????
3-Criterion of Realism
12
Suppose ? = 0.55
Alternative 1: 0.55 × 700 + 0.45 × −100 = 340
Alternative 2: 0.55 × 90 + 0.45 × 90 = 90
Alternatives
Outcomes
(States of nature) Criterion
for Realism
Oil Dry
Drill for oil $700 -$100 340
Sell the land $90 $90 90
Max
3-Criterion of Realism
13
Suppose ? = 0.15
Alternative 1: 0.15 × 700 + 0.85 × −100 = 20
Alternative 2: 0.15 × 90 + 0.15 × 90 = 90
Alternatives
Outcomes
(States of nature) Criterion
for Realism
Oil Dry
Drill for oil $700 -$100 20
Sell the land $90 $90 90
Max
4- Equally Likely (Laplace)
14
Calculate the average payoff for each alternative and select the alternative with
the highest average payoff.
Average Payoff =
σ ???????
?
where ? is the number of outcomes for the alternative
4- Equally Likely (Laplace)
15
Alternative 1:
700+(−100)
2
= 300
Alternative 2:
90+90
2
= 90
Alternatives
Outcomes
(States of nature) Laplace
Oil Dry
Drill for oil $700 -$100 300
Sell the land $90 $90 90
Max
5- Minimax Regret
16
Opportunity loss or regret
Is the amount lost by not picking the best alternative.
Minimax regret finds the alternative that minimizes the maximum regret for
each alternative.
First find the regrets for all outcome-alternative combinations by:
best payoff for outcome − actual payoff
Next, find the maximum regret for alternatives and choose the minimum
one among them.
5- Minimax Regret
17
Min
Alternatives
Regret of Outcomes Max
regretOil Dry
Drill for oil 700-700 = 0 90-(-100) = 190 190
Sell the land 700-90 = 610 90-90 = 0 610
Alternatives
Outcomes
(States of nature) Laplace
Oil Dry
Drill for oil $700 -$100 300
Sell the land $90 $90 90
Payoff Table
Opportunity Loss Table (Regret = best payoff for outcome − actual payoff)
Example 2
18
Alternatives
Outcomes
High
Demand
Moderate
Demand
Low
Demand
Build Large Plant 200,000 100,000 -120,000
Build Small Plant 90,000 50,000 -20,000
Do Nothing 0 0 0
1- Maximax
19
Alternatives
Outcomes
MaxHigh
Demand
Moderate
Demand
Low Demand
Build Large Plant 200,000 100,000 -120,000 200,000
Build Small Plant 90,000 50,000 -20,000 90,000
Do
Nothing
0 0 0 0
2- Maximin
20
Alternatives
Outcomes
MinHigh
Demand
Moderate
Demand
Low Demand
Build Large Plant 200,000 100,000 -120,000 -120,000
Build Small Plant 90,000 50,000 -20,000 -20,000
Do
Nothing
0 0 0 0
3- Criterion of Realism, ? = 0.45
21
Alternatives
Outcomes
RealismHigh
Demand
Moderate
Demand
Low Demand
Build Large Plant 200,000 100,000 -120,000 24,000
Build Small Plant 90,000 50,000 -20,000 29,500
Do
Nothing
0 0 0 0
Alternative 1: 0.45 × 200,000 + 0.55 × −120,000 = 24,000
Alternative 2: 0.45 × 90,000 + 0.55 × −20,000 = 29,500
4- Equally Likely (Laplace)
22
Alternatives
Outcomes
LaplaceHigh
Demand
Moderate
Demand
Low Demand
Build Large Plant 200,000 100,000 -120,000 60,000
Build Small Plant 90,000 50,000 -20,000 40,000
Do
Nothing
0 0 0 0
Alternative 1:
200,000+100,000+(−120,000)
3
= 60,000
Alternative 2:
90,000+50,000+(−20,000)
3
= 40,000
5- Minimax Regret
23
A
lt
e
r
n
a
ti
v
e
s
Regret of Outcomes
Max
High
Demand
Moderate
Demand
Low
Demand
Build
Large
Plant
200,000-200,000 = 0
100,000-100,000=
0
0-(-120,000)=
120,000
120,000
Build
Small
Plant
200,000-90,000=
110,000
100,000-0,000=
50,000
0-(-20,000) =
20,000
110,000
Do
Nothing 200,000-0= 200,000
100,000-0=
100,000
0-0=0 200,000
Using Excel
24
All formulas can be implemented in Excel.
There is a prepared Excel sheet on Avenue:
Solver-Decision Analysis Under Uncertainty.xlsx
Decision Making Under Risk
25
When the decision maker has some idea about the
probabilities of outcomes.
We use probabilities of outcomes to find the best
alternative.
1. Expected Monetary Value (EMV)
2. Expected Opportunity Loss (EOL)
3. Expected Value of Perfect Information (EVPI)
Expected Monetary Value (EMV)
26
EMV is the weighted average of all possible payoffs,
where weights are probabilities of outcomes
EMV for each alternative is
????????
??????????? × ??????
We would like to maximize the EMV
Select the alternative with largest EMV
Expected Monetary Value (EMV)
27
Alternatives
Outcomes
EMVHigh
Demand
Moderate
Demand
Low Demand
1- Build Large
Plant
200,000 100,000 -120,000 86,000
2- Build Small
Plant
90,000 50,000 -20,000 40,000
3- Do
Nothing
0 0 0 0
Probability 0.3 0.5 0.2
EMV 1 = 200,000 × 0.3 + 100,000 × 0.5 − 120,000 × 0.2 = 86,000
EMV 2 = 90,000 × 0.3 + 50,000 × 0.5 − 20,000 × 0.2 = 48,000
Expected Opportunity Loss (EOL)
28
Opportunity loss (Regret) is the difference between the optimal payoff
and the actual payoff.
EOL is the weighted (with probabilities) average of all regrets.
EOL is the expected cost of not picking the best solution.
EOL for each alternative is
????????
??????????? × ??????
We would like to minimize the EOL
Select the alternative with smallest EOL
Expected Opportunity Loss (EOL)
29
EOL 1 = 200,000 − 200,000 × 0.3 + 100,000 − 100,000 × 0.5 + (0 + 120,000) × 0.2 = 24,000
EOL 2 = (200,000-90,000) × 0.3 + 100,000 − 50,000 × 0.5 + (0 + 20,000) × 0.2 = 62,000
EOL 3 = 200,000 − 0 × 0.3 + 100,000 − 0 × 0.5 + (0 − 0) × 0.2 = 110,000
Alternatives
Regret of Outcomes
EOLHigh
Demand
Moderate
Demand
Low Demand
Build Large
Plant
200,000-200,000 100,000-100,000 0-(-120,000) 24,000
Build Small
Plant
200,000-90,000 100,000-0,000 0-(-20,000) 62,000
Do
Nothing 200,000-0 100,000-0 0-0 110,000
Probability 0.3 0.5 0.2
EMV vs EOL
30
In EMV, we choose the alternative with maximum EMV.
In EOL, we choose the alternative with minimum EOL.
In fact, these two always suggest the same alternative:
The alternative suggested by Max EMV
is the same as
the alternative suggested by Min EOL
Expected Value of Perfect Information (EVPI)
31
A company claims that they can predict what happens in the future with
certainty.
They have the perfect information, and they want to sell it to us!
We want to know the monetary value of this information.
If we have perfect information, we select alternative with the best payoff.
Expected Value with Perfect Information (EVwPI)
Weighted average of payoffs with certainty
????????
??????????? × ???? ??????
Expected Value of Perfect Information (EVPI)
32
EVwPI is the average payoff when we have the perfect information.
Max EMV (Min EOL) is what we can do without any information!
(expected value without perfect information)
There for EVwPI minus Max EMV is the maximum worth of
perfect information:
EVPI = EVwPI – Max EMV
We must not pay more than EVPI for the information.
EVPI is the upper bound for the money that we should spend for
the information.
EVPI = Min EOL
33
Alternatives
Outcomes
EMV EOLHigh
Demand
Moderate
Demand
Low
Demand
1- Build Large
Plant
200,000 100,000 -120,000 86,000 24,000
2- Build Small
Plant
90,000 50,000 -20,000 40,000 62,000
3- Do
Nothing
0 0 0 0 110,000
Probability 0.3 0.5 0.2
EVwPI = 200,000 × 0.3 + 100,000 × 0.5 + 0 × 0.2 = 110,000
EVPI= EVwPI- Max EMV = 110,000 − 86000 = 24,000
EVPI = Min EOL = 24,000
Expected Value of Perfect Information (EVPI)
Expected Value of Perfect Information (EVPI)
34
We have:
EVPI = EVwPI – Max EMV
EVPI = Min EOL
Therefore:
EVwPI = Max EMV + Min EOL
For any decision alternative:
EVwPI = EMV + EOL
35
Alternatives
Outcomes
EMV EOL EVwPI
High
Demand
Moderate
Demand
Low
Demand
1- Build
Large Plant
200,000 100,000 -120,000 86,000 24,000 110,000
2- Build
Small Plant
90,000 50,000 -20,000 40,000 62,000 110,000
3- Do
Nothing
0 0 0 0 110,000 110,000
EVwPI = EMV + EOL
Expected Value of Perfect Information (EVPI)
Expected Value of Perfect Information (EVPI)
36
EVwPI Max payoff with Perfect Information
EOL
EOL
EOL
EOL
EVPI
EMV
EMV
EMV
EMV
Alternative 1 Alternative 2 Alternative 3 Alternative 4
EVwPI = EMV + EOL
Example 3
37
We would like to decide on the order quantities for snowboards
over next 5 months.
Everything must go during the winter season.
The profit is $100.
Unsold snowboards will have a loss of $50.
Alternatives: Order quantity of 100,200,300,400,500
Outcome
1
Outcome
2
Outcome
3
Outcome
4
Outcome
5
Demand 100 200 300 400 500
Probability 0.2 0.3 0.3 0.1 0.1
Example 3 – Payoff Table
38
O
rd
e
r
S
iz
e
(A
lt
e
r
n
a
ti
v
e
s) Demand (outcomes)
Outcome 1 Outcome 2 Outcome 3 Outcome 4 Outcome 5
100 200 300 400 500
100 $10,000 $10,000 $10,000 $10,000 $10,000
200 $5,000 $20,000 $20,000 $20,000 $20,000
300 0 $15,000 $30,000 $30,000 $30,000
400 -$5,000 $10,000 $25,000 $40,000 $40,000
500 -$10,000 $5,000 $20,000 $35,000 $50,000
Probability 0.2 0.3 0.3 0.1 0.1
Payoff (Profit) =$100 × 200 − $50 × 200 = $10,000 (Demand < Order Size) Payoff (Profit) =$100 × 300 = $30,000 (Demand = Order Size) Payoff (Profit) =$100 × 200 = $20,000 (Demand > Order Size)
Example 3 – EMV
39
O
rd
e
r
S
iz
e
(A
lt
e
r
n
a
ti
v
e
s) Demand (outcomes)
Outcome 1 Outcome 2 Outcome 3 Outcome 4 Outcome 5
EMV
100 200 300 400 500
100 $10,000 $10,000 $10,000 $10,000 $10,000 $10,000
200 $5,000 $20,000 $20,000 $20,000 $20,000 $17,000
300 0 $15,000 $30,000 $30,000 $30,000 $19,500
400 -$5,000 $10,000 $25,000 $40,000 $40,000 $17,500
500 -$10,000 $5,000 $20,000 $35,000 $50,000 $14,000
Probability 0.2 0.3 0.3 0.1 0.1
Example 3 – EOL Table
40
O
rd
e
r
S
iz
e
(A
lt
e
r
n
a
ti
v
e
s) Demands (regret of outcomes)
Outcome 1 Outcome 2 Outcome 3 Outcome 4 Outcome 5
EOL
100 200 300 400 500
100 0 $10,000 $20,000 $30,000 $40,000 $16,000
200 $5,000 0 $10,000 $20,000 $30,000 $9,000
300 $10,000 $5,000 0 $10,000 $20,000 $6,500
400 $15,000 $10,000 $5,000 0 $10,000 $8,500
500 $20,000 $15,000 $10,000 $5,000 0 $12,000
Probability 0.2 0.3 0.3 0.1 0.1
Example 3 – EVPI
41
EVwPI = 10,000 × 0.2 + 20,000 × 0.3 + 30,000 × 0.3 +
40,000 × 0.1 + 50,000 × 0.1 = 26,000
or
EVwPI = EMV + EOL = 10,000 + 16,000 = 26,000
EVPI= EVwPI- Max EMV = 26,000 − 19,500 = 6,500
EVPI = Min EOL = 6,500
➢A perfect forecast of demand is worth no more than
$6,500.
Example 3 – EVPI
42
O
rd
e
r
S
iz
e
(A
lt
e
r
n
a
ti
v
e
s) Demand (outcomes)
Outcome
1
Outcome
2
Outcome 3 Outcome 4 Outcome 5
EMV EOL
100 200 300 400 500
100 $10,000 $10,000 $10,000 $10,000 $10,000 $10,000 $16,000
200 $5,000 $20,000 $20,000 $20,000 $20,000 $17,000 $9,000
300 0 $15,000 $30,000 $30,000 $30,000 $19,500 $6,500
400 -$5,000 $10,000 $25,000 $40,000 $40,000 $17,500 $8,500
500 -$10,000 $5,000 $20,000 $35,000 $50,000 $14,000 $12,000
Probability 0.2 0.3 0.3 0.1 0.1
EVwPI
Using Excel
43
All formulas can be implemented in Excel.
There is a prepared Excel sheet on Avenue:
Solver-Decision Analysis Under Risk-One Stage.xlt
Practice Problems
CHAPTER 8
Discussion Questions 4, 5
Problems 14, 15, 19, 20
44
3QA3/2DA3
Management Science for
Lecture 06
C01: July 7, 2021
C02: July 8, 2021
Instructors:
Seyyed Hossein Alavi Zdravko Dimitrov
Decision Analysis
Decision Analysis
3
We live in a world surrounded by uncertainties and risks.
We have to make a decision, without knowing for sure which
events will occur in the future.
We’d better consider all decision alternatives before we make a
decision.
Decision analysis is an analytic and systematic approach to the study
of decision making.
Steps of Decision Making
4
1. Clearly define the problem
2. List ALL possible alternatives
3. Identify all possible outcomes for each alternative
4. Identify the payoff for each alternative and outcome combination
5. Use a decision modeling technique to choose an alternative
Types of Decision Making
5
Under Certainty
We know the consequence of all alternatives.
Under Uncertainty
We do not know the probability of each outcome.
Under Risk
We know the probability of each outcome.
Decision Making Under Uncertainty
6
The manager can list the possible future outcomes but cannot
estimate the probability that a specific outcome will occur.
Five different decision-making criteria can be used to make a decision:
1. Maximax
2. Maximin
3. Realism
4. Equally likely
5. Minimax regret
Drilling Example
7
A drilling company has a land. The manager would like to consider
two alternatives:
1. Drill the land for oil
2. Sell the land
The possible outcomes (state of nature) are:
1. Oil
2. Dry
The payoffs are:
1. If the company finds oil: profit of $700
2. If the company cannot find oil: cost of $100
3. If the company sells the land: profit of $90
Drilling Example
8
Payoff Table:
Alternatives
Outcomes (States of nature)
Oil Dry
Drill for oil $700 -$100
Sell the land $90 $90
1-Maximax
9
For each alternative, find the maximum payoff over all possible outcomes. Next,
find the maximum of them. Choose the alternative whose maximum payoff gives
this maximum.
It is choosing the alternative with the best payoff, if the best outcome happens
(optimistic!)
Alternatives
Outcomes
(States of nature) Max
Oil Dry
Drill for oil $700 -$100 700
Sell the land $90 $90 90
Max
2-Maximin
10
For each alternative, find the minimum payoff over all possible outcomes. Next,
find the maximum of them. Chose the alternative whose minimum payoff gives
this maximum.
It is choosing the alternative with best payoff, if the worst outcome happens
(pessimistic!)
Alternatives
Outcomes
(States of nature) Min
Oil Dry
Drill for oil $700 -$100 -100
Sell the land $90 $90 90
Max
3-Criterion of Realism
11
Decision makers should not be optimists or pessimists. They should be realistic.
Define Coefficient of Realism: 0 ≤ ? ≤ 1
? = 1 means the decision maker is totally optimistic.(Maximax)
? = 0 means the decision maker is totally pessimistic.(Maximin)
Calculate the realism payoff for each alternative and select the alternative with the
highest realism payoff.
Realism Payoff = ? × ??? ?????? + 1 − ? × ??? ??????
3-Criterion of Realism
12
Suppose ? = 0.55
Alternative 1: 0.55 × 700 + 0.45 × −100 = 340
Alternative 2: 0.55 × 90 + 0.45 × 90 = 90
Alternatives
Outcomes
(States of nature) Criterion
for Realism
Oil Dry
Drill for oil $700 -$100 340
Sell the land $90 $90 90
Max
3-Criterion of Realism
13
Suppose ? = 0.15
Alternative 1: 0.15 × 700 + 0.85 × −100 = 20
Alternative 2: 0.15 × 90 + 0.15 × 90 = 90
Alternatives
Outcomes
(States of nature) Criterion
for Realism
Oil Dry
Drill for oil $700 -$100 20
Sell the land $90 $90 90
Max
4- Equally Likely (Laplace)
14
Calculate the average payoff for each alternative and select the alternative with
the highest average payoff.
Average Payoff =
σ ???????
?
where ? is the number of outcomes for the alternative
4- Equally Likely (Laplace)
15
Alternative 1:
700+(−100)
2
= 300
Alternative 2:
90+90
2
= 90
Alternatives
Outcomes
(States of nature) Laplace
Oil Dry
Drill for oil $700 -$100 300
Sell the land $90 $90 90
Max
5- Minimax Regret
16
Opportunity loss or regret
Is the amount lost by not picking the best alternative.
Minimax regret finds the alternative that minimizes the maximum regret for
each alternative.
First find the regrets for all outcome-alternative combinations by:
best payoff for outcome − actual payoff
Next, find the maximum regret for alternatives and choose the minimum
one among them.
5- Minimax Regret
17
Min
Alternatives
Regret of Outcomes Max
regretOil Dry
Drill for oil 700-700 = 0 90-(-100) = 190 190
Sell the land 700-90 = 610 90-90 = 0 610
Alternatives
Outcomes
(States of nature) Laplace
Oil Dry
Drill for oil $700 -$100 300
Sell the land $90 $90 90
Payoff Table
Opportunity Loss Table (Regret = best payoff for outcome − actual payoff)
Example 2
18
Alternatives
Outcomes
High
Demand
Moderate
Demand
Low
Demand
Build Large Plant 200,000 100,000 -120,000
Build Small Plant 90,000 50,000 -20,000
Do Nothing 0 0 0
1- Maximax
19
Alternatives
Outcomes
MaxHigh
Demand
Moderate
Demand
Low Demand
Build Large Plant 200,000 100,000 -120,000 200,000
Build Small Plant 90,000 50,000 -20,000 90,000
Do
Nothing
0 0 0 0
2- Maximin
20
Alternatives
Outcomes
MinHigh
Demand
Moderate
Demand
Low Demand
Build Large Plant 200,000 100,000 -120,000 -120,000
Build Small Plant 90,000 50,000 -20,000 -20,000
Do
Nothing
0 0 0 0
3- Criterion of Realism, ? = 0.45
21
Alternatives
Outcomes
RealismHigh
Demand
Moderate
Demand
Low Demand
Build Large Plant 200,000 100,000 -120,000 24,000
Build Small Plant 90,000 50,000 -20,000 29,500
Do
Nothing
0 0 0 0
Alternative 1: 0.45 × 200,000 + 0.55 × −120,000 = 24,000
Alternative 2: 0.45 × 90,000 + 0.55 × −20,000 = 29,500
4- Equally Likely (Laplace)
22
Alternatives
Outcomes
LaplaceHigh
Demand
Moderate
Demand
Low Demand
Build Large Plant 200,000 100,000 -120,000 60,000
Build Small Plant 90,000 50,000 -20,000 40,000
Do
Nothing
0 0 0 0
Alternative 1:
200,000+100,000+(−120,000)
3
= 60,000
Alternative 2:
90,000+50,000+(−20,000)
3
= 40,000
5- Minimax Regret
23
A
lt
e
r
n
a
ti
v
e
s
Regret of Outcomes
Max
High
Demand
Moderate
Demand
Low
Demand
Build
Large
Plant
200,000-200,000 = 0
100,000-100,000=
0
0-(-120,000)=
120,000
120,000
Build
Small
Plant
200,000-90,000=
110,000
100,000-0,000=
50,000
0-(-20,000) =
20,000
110,000
Do
Nothing 200,000-0= 200,000
100,000-0=
100,000
0-0=0 200,000
Using Excel
24
All formulas can be implemented in Excel.
There is a prepared Excel sheet on Avenue:
Solver-Decision Analysis Under Uncertainty.xlsx
Decision Making Under Risk
25
When the decision maker has some idea about the
probabilities of outcomes.
We use probabilities of outcomes to find the best
alternative.
1. Expected Monetary Value (EMV)
2. Expected Opportunity Loss (EOL)
3. Expected Value of Perfect Information (EVPI)
Expected Monetary Value (EMV)
26
EMV is the weighted average of all possible payoffs,
where weights are probabilities of outcomes
EMV for each alternative is
????????
??????????? × ??????
We would like to maximize the EMV
Select the alternative with largest EMV
Expected Monetary Value (EMV)
27
Alternatives
Outcomes
EMVHigh
Demand
Moderate
Demand
Low Demand
1- Build Large
Plant
200,000 100,000 -120,000 86,000
2- Build Small
Plant
90,000 50,000 -20,000 40,000
3- Do
Nothing
0 0 0 0
Probability 0.3 0.5 0.2
EMV 1 = 200,000 × 0.3 + 100,000 × 0.5 − 120,000 × 0.2 = 86,000
EMV 2 = 90,000 × 0.3 + 50,000 × 0.5 − 20,000 × 0.2 = 48,000
Expected Opportunity Loss (EOL)
28
Opportunity loss (Regret) is the difference between the optimal payoff
and the actual payoff.
EOL is the weighted (with probabilities) average of all regrets.
EOL is the expected cost of not picking the best solution.
EOL for each alternative is
????????
??????????? × ??????
We would like to minimize the EOL
Select the alternative with smallest EOL
Expected Opportunity Loss (EOL)
29
EOL 1 = 200,000 − 200,000 × 0.3 + 100,000 − 100,000 × 0.5 + (0 + 120,000) × 0.2 = 24,000
EOL 2 = (200,000-90,000) × 0.3 + 100,000 − 50,000 × 0.5 + (0 + 20,000) × 0.2 = 62,000
EOL 3 = 200,000 − 0 × 0.3 + 100,000 − 0 × 0.5 + (0 − 0) × 0.2 = 110,000
Alternatives
Regret of Outcomes
EOLHigh
Demand
Moderate
Demand
Low Demand
Build Large
Plant
200,000-200,000 100,000-100,000 0-(-120,000) 24,000
Build Small
Plant
200,000-90,000 100,000-0,000 0-(-20,000) 62,000
Do
Nothing 200,000-0 100,000-0 0-0 110,000
Probability 0.3 0.5 0.2
EMV vs EOL
30
In EMV, we choose the alternative with maximum EMV.
In EOL, we choose the alternative with minimum EOL.
In fact, these two always suggest the same alternative:
The alternative suggested by Max EMV
is the same as
the alternative suggested by Min EOL
Expected Value of Perfect Information (EVPI)
31
A company claims that they can predict what happens in the future with
certainty.
They have the perfect information, and they want to sell it to us!
We want to know the monetary value of this information.
If we have perfect information, we select alternative with the best payoff.
Expected Value with Perfect Information (EVwPI)
Weighted average of payoffs with certainty
????????
??????????? × ???? ??????
Expected Value of Perfect Information (EVPI)
32
EVwPI is the average payoff when we have the perfect information.
Max EMV (Min EOL) is what we can do without any information!
(expected value without perfect information)
There for EVwPI minus Max EMV is the maximum worth of
perfect information:
EVPI = EVwPI – Max EMV
We must not pay more than EVPI for the information.
EVPI is the upper bound for the money that we should spend for
the information.
EVPI = Min EOL
33
Alternatives
Outcomes
EMV EOLHigh
Demand
Moderate
Demand
Low
Demand
1- Build Large
Plant
200,000 100,000 -120,000 86,000 24,000
2- Build Small
Plant
90,000 50,000 -20,000 40,000 62,000
3- Do
Nothing
0 0 0 0 110,000
Probability 0.3 0.5 0.2
EVwPI = 200,000 × 0.3 + 100,000 × 0.5 + 0 × 0.2 = 110,000
EVPI= EVwPI- Max EMV = 110,000 − 86000 = 24,000
EVPI = Min EOL = 24,000
Expected Value of Perfect Information (EVPI)
Expected Value of Perfect Information (EVPI)
34
We have:
EVPI = EVwPI – Max EMV
EVPI = Min EOL
Therefore:
EVwPI = Max EMV + Min EOL
For any decision alternative:
EVwPI = EMV + EOL
35
Alternatives
Outcomes
EMV EOL EVwPI
High
Demand
Moderate
Demand
Low
Demand
1- Build
Large Plant
200,000 100,000 -120,000 86,000 24,000 110,000
2- Build
Small Plant
90,000 50,000 -20,000 40,000 62,000 110,000
3- Do
Nothing
0 0 0 0 110,000 110,000
EVwPI = EMV + EOL
Expected Value of Perfect Information (EVPI)
Expected Value of Perfect Information (EVPI)
36
EVwPI Max payoff with Perfect Information
EOL
EOL
EOL
EOL
EVPI
EMV
EMV
EMV
EMV
Alternative 1 Alternative 2 Alternative 3 Alternative 4
EVwPI = EMV + EOL
Example 3
37
We would like to decide on the order quantities for snowboards
over next 5 months.
Everything must go during the winter season.
The profit is $100.
Unsold snowboards will have a loss of $50.
Alternatives: Order quantity of 100,200,300,400,500
Outcome
1
Outcome
2
Outcome
3
Outcome
4
Outcome
5
Demand 100 200 300 400 500
Probability 0.2 0.3 0.3 0.1 0.1
Example 3 – Payoff Table
38
O
rd
e
r
S
iz
e
(A
lt
e
r
n
a
ti
v
e
s) Demand (outcomes)
Outcome 1 Outcome 2 Outcome 3 Outcome 4 Outcome 5
100 200 300 400 500
100 $10,000 $10,000 $10,000 $10,000 $10,000
200 $5,000 $20,000 $20,000 $20,000 $20,000
300 0 $15,000 $30,000 $30,000 $30,000
400 -$5,000 $10,000 $25,000 $40,000 $40,000
500 -$10,000 $5,000 $20,000 $35,000 $50,000
Probability 0.2 0.3 0.3 0.1 0.1
Payoff (Profit) =$100 × 200 − $50 × 200 = $10,000 (Demand < Order Size) Payoff (Profit) =$100 × 300 = $30,000 (Demand = Order Size) Payoff (Profit) =$100 × 200 = $20,000 (Demand > Order Size)
Example 3 – EMV
39
O
rd
e
r
S
iz
e
(A
lt
e
r
n
a
ti
v
e
s) Demand (outcomes)
Outcome 1 Outcome 2 Outcome 3 Outcome 4 Outcome 5
EMV
100 200 300 400 500
100 $10,000 $10,000 $10,000 $10,000 $10,000 $10,000
200 $5,000 $20,000 $20,000 $20,000 $20,000 $17,000
300 0 $15,000 $30,000 $30,000 $30,000 $19,500
400 -$5,000 $10,000 $25,000 $40,000 $40,000 $17,500
500 -$10,000 $5,000 $20,000 $35,000 $50,000 $14,000
Probability 0.2 0.3 0.3 0.1 0.1
Example 3 – EOL Table
40
O
rd
e
r
S
iz
e
(A
lt
e
r
n
a
ti
v
e
s) Demands (regret of outcomes)
Outcome 1 Outcome 2 Outcome 3 Outcome 4 Outcome 5
EOL
100 200 300 400 500
100 0 $10,000 $20,000 $30,000 $40,000 $16,000
200 $5,000 0 $10,000 $20,000 $30,000 $9,000
300 $10,000 $5,000 0 $10,000 $20,000 $6,500
400 $15,000 $10,000 $5,000 0 $10,000 $8,500
500 $20,000 $15,000 $10,000 $5,000 0 $12,000
Probability 0.2 0.3 0.3 0.1 0.1
Example 3 – EVPI
41
EVwPI = 10,000 × 0.2 + 20,000 × 0.3 + 30,000 × 0.3 +
40,000 × 0.1 + 50,000 × 0.1 = 26,000
or
EVwPI = EMV + EOL = 10,000 + 16,000 = 26,000
EVPI= EVwPI- Max EMV = 26,000 − 19,500 = 6,500
EVPI = Min EOL = 6,500
➢A perfect forecast of demand is worth no more than
$6,500.
Example 3 – EVPI
42
O
rd
e
r
S
iz
e
(A
lt
e
r
n
a
ti
v
e
s) Demand (outcomes)
Outcome
1
Outcome
2
Outcome 3 Outcome 4 Outcome 5
EMV EOL
100 200 300 400 500
100 $10,000 $10,000 $10,000 $10,000 $10,000 $10,000 $16,000
200 $5,000 $20,000 $20,000 $20,000 $20,000 $17,000 $9,000
300 0 $15,000 $30,000 $30,000 $30,000 $19,500 $6,500
400 -$5,000 $10,000 $25,000 $40,000 $40,000 $17,500 $8,500
500 -$10,000 $5,000 $20,000 $35,000 $50,000 $14,000 $12,000
Probability 0.2 0.3 0.3 0.1 0.1
EVwPI
Using Excel
43
All formulas can be implemented in Excel.
There is a prepared Excel sheet on Avenue:
Solver-Decision Analysis Under Risk-One Stage.xlt
Practice Problems
CHAPTER 8
Discussion Questions 4, 5
Problems 14, 15, 19, 20
44
3QA3/2DA3
Management Science for
Lecture 06
C01: July 7, 2021
C02: July 8, 2021
Instructors:
Seyyed Hossein Alavi Zdravko Dimitrov
Decision Analysis
Decision Analysis
3
We live in a world surrounded by uncertainties and risks.
We have to make a decision, without knowing for sure which
events will occur in the future.
We’d better consider all decision alternatives before we make a
decision.
Decision analysis is an analytic and systematic approach to the study
of decision making.
Steps of Decision Making
4
1. Clearly define the problem
2. List ALL possible alternatives
3. Identify all possible outcomes for each alternative
4. Identify the payoff for each alternative and outcome combination
5. Use a decision modeling technique to choose an alternative
Types of Decision Making
5
Under Certainty
We know the consequence of all alternatives.
Under Uncertainty
We do not know the probability of each outcome.
Under Risk
We know the probability of each outcome.
Decision Making Under Uncertainty
6
The manager can list the possible future outcomes but cannot
estimate the probability that a specific outcome will occur.
Five different decision-making criteria can be used to make a decision:
1. Maximax
2. Maximin
3. Realism
4. Equally likely
5. Minimax regret
Drilling Example
7
A drilling company has a land. The manager would like to consider
two alternatives:
1. Drill the land for oil
2. Sell the land
The possible outcomes (state of nature) are:
1. Oil
2. Dry
The payoffs are:
1. If the company finds oil: profit of $700
2. If the company cannot find oil: cost of $100
3. If the company sells the land: profit of $90
Drilling Example
8
Payoff Table:
Alternatives
Outcomes (States of nature)
Oil Dry
Drill for oil $700 -$100
Sell the land $90 $90
1-Maximax
9
For each alternative, find the maximum payoff over all possible outcomes. Next,
find the maximum of them. Choose the alternative whose maximum payoff gives
this maximum.
It is choosing the alternative with the best payoff, if the best outcome happens
(optimistic!)
Alternatives
Outcomes
(States of nature) Max
Oil Dry
Drill for oil $700 -$100 700
Sell the land $90 $90 90
Max
2-Maximin
10
For each alternative, find the minimum payoff over all possible outcomes. Next,
find the maximum of them. Chose the alternative whose minimum payoff gives
this maximum.
It is choosing the alternative with best payoff, if the worst outcome happens
(pessimistic!)
Alternatives
Outcomes
(States of nature) Min
Oil Dry
Drill for oil $700 -$100 -100
Sell the land $90 $90 90
Max
3-Criterion of Realism
11
Decision makers should not be optimists or pessimists. They should be realistic.
Define Coefficient of Realism: 0 ≤ ? ≤ 1
? = 1 means the decision maker is totally optimistic.(Maximax)
? = 0 means the decision maker is totally pessimistic.(Maximin)
Calculate the realism payoff for each alternative and select the alternative with the
highest realism payoff.
Realism Payoff = ? × ??? ?????? + 1 − ? × ??? ??????
3-Criterion of Realism
12
Suppose ? = 0.55
Alternative 1: 0.55 × 700 + 0.45 × −100 = 340
Alternative 2: 0.55 × 90 + 0.45 × 90 = 90
Alternatives
Outcomes
(States of nature) Criterion
for Realism
Oil Dry
Drill for oil $700 -$100 340
Sell the land $90 $90 90
Max
3-Criterion of Realism
13
Suppose ? = 0.15
Alternative 1: 0.15 × 700 + 0.85 × −100 = 20
Alternative 2: 0.15 × 90 + 0.15 × 90 = 90
Alternatives
Outcomes
(States of nature) Criterion
for Realism
Oil Dry
Drill for oil $700 -$100 20
Sell the land $90 $90 90
Max
4- Equally Likely (Laplace)
14
Calculate the average payoff for each alternative and select the alternative with
the highest average payoff.
Average Payoff =
σ ???????
?
where ? is the number of outcomes for the alternative
4- Equally Likely (Laplace)
15
Alternative 1:
700+(−100)
2
= 300
Alternative 2:
90+90
2
= 90
Alternatives
Outcomes
(States of nature) Laplace
Oil Dry
Drill for oil $700 -$100 300
Sell the land $90 $90 90
Max
5- Minimax Regret
16
Opportunity loss or regret
Is the amount lost by not picking the best alternative.
Minimax regret finds the alternative that minimizes the maximum regret for
each alternative.
First find the regrets for all outcome-alternative combinations by:
best payoff for outcome − actual payoff
Next, find the maximum regret for alternatives and choose the minimum
one among them.
5- Minimax Regret
17
Min
Alternatives
Regret of Outcomes Max
regretOil Dry
Drill for oil 700-700 = 0 90-(-100) = 190 190
Sell the land 700-90 = 610 90-90 = 0 610
Alternatives
Outcomes
(States of nature) Laplace
Oil Dry
Drill for oil $700 -$100 300
Sell the land $90 $90 90
Payoff Table
Opportunity Loss Table (Regret = best payoff for outcome − actual payoff)
Example 2
18
Alternatives
Outcomes
High
Demand
Moderate
Demand
Low
Demand
Build Large Plant 200,000 100,000 -120,000
Build Small Plant 90,000 50,000 -20,000
Do Nothing 0 0 0
1- Maximax
19
Alternatives
Outcomes
MaxHigh
Demand
Moderate
Demand
Low Demand
Build Large Plant 200,000 100,000 -120,000 200,000
Build Small Plant 90,000 50,000 -20,000 90,000
Do
Nothing
0 0 0 0
2- Maximin
20
Alternatives
Outcomes
MinHigh
Demand
Moderate
Demand
Low Demand
Build Large Plant 200,000 100,000 -120,000 -120,000
Build Small Plant 90,000 50,000 -20,000 -20,000
Do
Nothing
0 0 0 0
3- Criterion of Realism, ? = 0.45
21
Alternatives
Outcomes
RealismHigh
Demand
Moderate
Demand
Low Demand
Build Large Plant 200,000 100,000 -120,000 24,000
Build Small Plant 90,000 50,000 -20,000 29,500
Do
Nothing
0 0 0 0
Alternative 1: 0.45 × 200,000 + 0.55 × −120,000 = 24,000
Alternative 2: 0.45 × 90,000 + 0.55 × −20,000 = 29,500
4- Equally Likely (Laplace)
22
Alternatives
Outcomes
LaplaceHigh
Demand
Moderate
Demand
Low Demand
Build Large Plant 200,000 100,000 -120,000 60,000
Build Small Plant 90,000 50,000 -20,000 40,000
Do
Nothing
0 0 0 0
Alternative 1:
200,000+100,000+(−120,000)
3
= 60,000
Alternative 2:
90,000+50,000+(−20,000)
3
= 40,000
5- Minimax Regret
23
A
lt
e
r
n
a
ti
v
e
s
Regret of Outcomes
Max
High
Demand
Moderate
Demand
Low
Demand
Build
Large
Plant
200,000-200,000 = 0
100,000-100,000=
0
0-(-120,000)=
120,000
120,000
Build
Small
Plant
200,000-90,000=
110,000
100,000-0,000=
50,000
0-(-20,000) =
20,000
110,000
Do
Nothing 200,000-0= 200,000
100,000-0=
100,000
0-0=0 200,000
Using Excel
24
All formulas can be implemented in Excel.
There is a prepared Excel sheet on Avenue:
Solver-Decision Analysis Under Uncertainty.xlsx
Decision Making Under Risk
25
When the decision maker has some idea about the
probabilities of outcomes.
We use probabilities of outcomes to find the best
alternative.
1. Expected Monetary Value (EMV)
2. Expected Opportunity Loss (EOL)
3. Expected Value of Perfect Information (EVPI)
Expected Monetary Value (EMV)
26
EMV is the weighted average of all possible payoffs,
where weights are probabilities of outcomes
EMV for each alternative is
????????
??????????? × ??????
We would like to maximize the EMV
Select the alternative with largest EMV
Expected Monetary Value (EMV)
27
Alternatives
Outcomes
EMVHigh
Demand
Moderate
Demand
Low Demand
1- Build Large
Plant
200,000 100,000 -120,000 86,000
2- Build Small
Plant
90,000 50,000 -20,000 40,000
3- Do
Nothing
0 0 0 0
Probability 0.3 0.5 0.2
EMV 1 = 200,000 × 0.3 + 100,000 × 0.5 − 120,000 × 0.2 = 86,000
EMV 2 = 90,000 × 0.3 + 50,000 × 0.5 − 20,000 × 0.2 = 48,000
Expected Opportunity Loss (EOL)
28
Opportunity loss (Regret) is the difference between the optimal payoff
and the actual payoff.
EOL is the weighted (with probabilities) average of all regrets.
EOL is the expected cost of not picking the best solution.
EOL for each alternative is
????????
??????????? × ??????
We would like to minimize the EOL
Select the alternative with smallest EOL
Expected Opportunity Loss (EOL)
29
EOL 1 = 200,000 − 200,000 × 0.3 + 100,000 − 100,000 × 0.5 + (0 + 120,000) × 0.2 = 24,000
EOL 2 = (200,000-90,000) × 0.3 + 100,000 − 50,000 × 0.5 + (0 + 20,000) × 0.2 = 62,000
EOL 3 = 200,000 − 0 × 0.3 + 100,000 − 0 × 0.5 + (0 − 0) × 0.2 = 110,000
Alternatives
Regret of Outcomes
EOLHigh
Demand
Moderate
Demand
Low Demand
Build Large
Plant
200,000-200,000 100,000-100,000 0-(-120,000) 24,000
Build Small
Plant
200,000-90,000 100,000-0,000 0-(-20,000) 62,000
Do
Nothing 200,000-0 100,000-0 0-0 110,000
Probability 0.3 0.5 0.2
EMV vs EOL
30
In EMV, we choose the alternative with maximum EMV.
In EOL, we choose the alternative with minimum EOL.
In fact, these two always suggest the same alternative:
The alternative suggested by Max EMV
is the same as
the alternative suggested by Min EOL
Expected Value of Perfect Information (EVPI)
31
A company claims that they can predict what happens in the future with
certainty.
They have the perfect information, and they want to sell it to us!
We want to know the monetary value of this information.
If we have perfect information, we select alternative with the best payoff.
Expected Value with Perfect Information (EVwPI)
Weighted average of payoffs with certainty
????????
??????????? × ???? ??????
Expected Value of Perfect Information (EVPI)
32
EVwPI is the average payoff when we have the perfect information.
Max EMV (Min EOL) is what we can do without any information!
(expected value without perfect information)
There for EVwPI minus Max EMV is the maximum worth of
perfect information:
EVPI = EVwPI – Max EMV
We must not pay more than EVPI for the information.
EVPI is the upper bound for the money that we should spend for
the information.
EVPI = Min EOL
33
Alternatives
Outcomes
EMV EOLHigh
Demand
Moderate
Demand
Low
Demand
1- Build Large
Plant
200,000 100,000 -120,000 86,000 24,000
2- Build Small
Plant
90,000 50,000 -20,000 40,000 62,000
3- Do
Nothing
0 0 0 0 110,000
Probability 0.3 0.5 0.2
EVwPI = 200,000 × 0.3 + 100,000 × 0.5 + 0 × 0.2 = 110,000
EVPI= EVwPI- Max EMV = 110,000 − 86000 = 24,000
EVPI = Min EOL = 24,000
Expected Value of Perfect Information (EVPI)
Expected Value of Perfect Information (EVPI)
34
We have:
EVPI = EVwPI – Max EMV
EVPI = Min EOL
Therefore:
EVwPI = Max EMV + Min EOL
For any decision alternative:
EVwPI = EMV + EOL
35
Alternatives
Outcomes
EMV EOL EVwPI
High
Demand
Moderate
Demand
Low
Demand
1- Build
Large Plant
200,000 100,000 -120,000 86,000 24,000 110,000
2- Build
Small Plant
90,000 50,000 -20,000 40,000 62,000 110,000
3- Do
Nothing
0 0 0 0 110,000 110,000
EVwPI = EMV + EOL
Expected Value of Perfect Information (EVPI)
Expected Value of Perfect Information (EVPI)
36
EVwPI Max payoff with Perfect Information
EOL
EOL
EOL
EOL
EVPI
EMV
EMV
EMV
EMV
Alternative 1 Alternative 2 Alternative 3 Alternative 4
EVwPI = EMV + EOL
Example 3
37
We would like to decide on the order quantities for snowboards
over next 5 months.
Everything must go during the winter season.
The profit is $100.
Unsold snowboards will have a loss of $50.
Alternatives: Order quantity of 100,200,300,400,500
Outcome
1
Outcome
2
Outcome
3
Outcome
4
Outcome
5
Demand 100 200 300 400 500
Probability 0.2 0.3 0.3 0.1 0.1
Example 3 – Payoff Table
38
O
rd
e
r
S
iz
e
(A
lt
e
r
n
a
ti
v
e
s) Demand (outcomes)
Outcome 1 Outcome 2 Outcome 3 Outcome 4 Outcome 5
100 200 300 400 500
100 $10,000 $10,000 $10,000 $10,000 $10,000
200 $5,000 $20,000 $20,000 $20,000 $20,000
300 0 $15,000 $30,000 $30,000 $30,000
400 -$5,000 $10,000 $25,000 $40,000 $40,000
500 -$10,000 $5,000 $20,000 $35,000 $50,000
Probability 0.2 0.3 0.3 0.1 0.1
Payoff (Profit) =$100 × 200 − $50 × 200 = $10,000 (Demand < Order Size) Payoff (Profit) =$100 × 300 = $30,000 (Demand = Order Size) Payoff (Profit) =$100 × 200 = $20,000 (Demand > Order Size)
Example 3 – EMV
39
O
rd
e
r
S
iz
e
(A
lt
e
r
n
a
ti
v
e
s) Demand (outcomes)
Outcome 1 Outcome 2 Outcome 3 Outcome 4 Outcome 5
EMV
100 200 300 400 500
100 $10,000 $10,000 $10,000 $10,000 $10,000 $10,000
200 $5,000 $20,000 $20,000 $20,000 $20,000 $17,000
300 0 $15,000 $30,000 $30,000 $30,000 $19,500
400 -$5,000 $10,000 $25,000 $40,000 $40,000 $17,500
500 -$10,000 $5,000 $20,000 $35,000 $50,000 $14,000
Probability 0.2 0.3 0.3 0.1 0.1
Example 3 – EOL Table
40
O
rd
e
r
S
iz
e
(A
lt
e
r
n
a
ti
v
e
s) Demands (regret of outcomes)
Outcome 1 Outcome 2 Outcome 3 Outcome 4 Outcome 5
EOL
100 200 300 400 500
100 0 $10,000 $20,000 $30,000 $40,000 $16,000
200 $5,000 0 $10,000 $20,000 $30,000 $9,000
300 $10,000 $5,000 0 $10,000 $20,000 $6,500
400 $15,000 $10,000 $5,000 0 $10,000 $8,500
500 $20,000 $15,000 $10,000 $5,000 0 $12,000
Probability 0.2 0.3 0.3 0.1 0.1
Example 3 – EVPI
41
EVwPI = 10,000 × 0.2 + 20,000 × 0.3 + 30,000 × 0.3 +
40,000 × 0.1 + 50,000 × 0.1 = 26,000
or
EVwPI = EMV + EOL = 10,000 + 16,000 = 26,000
EVPI= EVwPI- Max EMV = 26,000 − 19,500 = 6,500
EVPI = Min EOL = 6,500
➢A perfect forecast of demand is worth no more than
$6,500.
Example 3 – EVPI
42
O
rd
e
r
S
iz
e
(A
lt
e
r
n
a
ti
v
e
s) Demand (outcomes)
Outcome
1
Outcome
2
Outcome 3 Outcome 4 Outcome 5
EMV EOL
100 200 300 400 500
100 $10,000 $10,000 $10,000 $10,000 $10,000 $10,000 $16,000
200 $5,000 $20,000 $20,000 $20,000 $20,000 $17,000 $9,000
300 0 $15,000 $30,000 $30,000 $30,000 $19,500 $6,500
400 -$5,000 $10,000 $25,000 $40,000 $40,000 $17,500 $8,500
500 -$10,000 $5,000 $20,000 $35,000 $50,000 $14,000 $12,000
Probability 0.2 0.3 0.3 0.1 0.1
EVwPI
Using Excel
43
All formulas can be implemented in Excel.
There is a prepared Excel sheet on Avenue:
Solver-Decision Analysis Under Risk-One Stage.xlt
Practice Problems
CHAPTER 8
Discussion Questions 4, 5
Problems 14, 15, 19, 20
44
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