Decision TreeRain Ruined refreshments Unhappines No Rain Very pleasant party 1 Rain Crowded but dry Proper feeling of being sensible g No Rain Crowded, hot Regrets about what might have
Trang 1Quantitative Business Analysis
(QBA)
I Lindner and J.R van den Brink
Trang 3Q tit ti B i A l i
Quantitative Business Analysis
• T torials: T esda s and Wednesda s
• Prepare exercises beforehand!
• Program for the first two weeks: Exercises from chapter “Topic E1 –
Exercises Decision Analysis”:
week 1: 1.1, 1.2, 1.3, 1.5, 1.8
week 2: 1.4, 1.6, 1.7, 1.9
Quantitative Methods (QBA) 3
Trang 4Quantitative Business Analysis
Contents of the Course
Week 1-2 (Ines Lindner)
1 Decision Analysis using Decision Trees
Week 3-6 (René van den Brink)
2 Strategic Thinking - Noncooperative Games
Quantitative Methods (QBA) 4
Trang 5Quantitative Business Analysis
• Book “Quantitative Business Analyses”
by C van Montfort and J.R van den Brink:
chapter T1 T2 E1 and E2;
• Book is available at Aureus
• Sheets of lectures (on Blackboard)
• Relevant sections for decision theory: 8.1-8.3, 8.5 (except “Using Excel ”), 8.6, 8.8- , ( p g ), ,
8.10
• We don’t discuss software applications in this
Quantitative Methods (QBA) 5
course!
Trang 6Quantitative Business Analysis
Two efficient strategies to pass
the exam!
the exam!
Quantitative Methods (QBA) 6
Trang 7Quantitative Business Analysis
Facts:
• You have to read the text material in You have to read the text material in
order to pass the exam
you already know 50 percent
Conclusion: Read text material before
lecture and take lecture as revision
Quantitative Methods (QBA) 7
lecture and take lecture as revision
Trang 8Quantitative Business Analysis
enough for exam.
Conclusion: Try to do the exercises yourself and take tutorial as a feedback on your
8
and take tutorial as a feedback on your
performance
Trang 9Quantitative Business Analysis
→ Answers to exercises decision theory will
be available at the end of week 2
be available at the end of week 2
9
Trang 10Decision Theory
Central question: What is the best decision to take?
Assumptions:
• We have some information
• We are able to compute with perfect accuracy
• We are fully rational
Quantitative Methods (QBA) 10
Trang 11What kinds of decisions need a
What kinds of decisions need a
theory?
Optimization – examples
• What is the best product mix?
• What is an optimal way to spend my money p y p y y
(intertemporal choice)?
Quantitative Methods (QBA) 11
Trang 12What kinds of decisions need a
What kinds of decisions need a
theory?
Choice under risk – examples
• Should I play the lottery? p y y
• What kind of insurrence should I buy?
Quantitative Methods (QBA) 12
Trang 13What kinds of decisions need a
What kinds of decisions need a
Quantitative Methods (QBA) 13
(depends on your boss)?
Trang 14What kinds of decisions need a
What kinds of decisions need a
theory?
Game theory: y
• Additional difficulty: the need to take into
account how other people in the situation will act
• Presence of several “players” (strategically acting agents)
• Requires strategic analysis (week 3-6).
Quantitative Methods (QBA) 14
Trang 15Decision Theory
Central question: What is the best decision to take?
• Absence of strategic considerations
• Can be seen as a one-player game.
Quantitative Methods (QBA) 15
Trang 16Decision Analysis using Decision Trees
Dilemma: organize party indoors or in
garden? What if it rains?
g
Events and Results
but content
Regrets
Quantitative Methods (QBA) 16
Trang 17Decision Analysis using Decision Trees
Dilemma: organize party indoors or in
garden? What if it rains?
g
Events and Results
but content
Regrets
Quantitative Methods (QBA) 17
Trang 18Decision Analysis using Decision Trees
Dilemma: organize party indoors or in
garden? What if it rains?
g
Events and Results
but content
Regrets
Quantitative Methods (QBA) 18
Trang 19Decision Tree Components
Trang 20Decision Tree
Rain
Ruined refreshments
Unhappines
No Rain
Very pleasant party
1
Rain
Crowded but dry
Proper feeling of being sensible g
No Rain
Crowded, hot Regrets about what might have been
Quantitative Methods (QBA) 20
Trang 21Decision Tree
Rain
Ruined refreshments
Unhappines
No Rain
Very pleasant party
1
P ff ?
1
Rain
Crowded but dry
Proper feeling of being sensible
Payoffs ?
g
No Rain
Crowded, hot Regrets about what might have been
Quantitative Methods (QBA) 21
Trang 22Decision Tree
Rain
Ruined refreshments
Unhappines
No Rain
Very pleasant party
1
Hi h
1
Rain
Crowded but dry
Proper feeling of being sensible
Highest payoff
g
No Rain
Crowded, hot Regrets about what might have been
Quantitative Methods (QBA) 22
Trang 23Decision Tree
Rain
Ruined refreshments
Unhappines
No Rain
Very pleasant party
1
L
1
Rain
Crowded but dry
Proper feeling of being sensible
Lowest payoff
g
No Rain
Crowded, hot Regrets about what might have been
Quantitative Methods (QBA) 23
Trang 24Very pleasant party
1
100
1
Rain
Crowded but dry
Proper feeling of being sensible
50
g
No Rain
Crowded, hot Regrets about what
Quantitative Methods (QBA) 24
Trang 25Possible Interpretation of Payoffs: p y
How much is this outcome worth to me?
Very pleasant party
1
100
1
Rain
Crowded but dry
Proper feeling of being sensible
50
g
No Rain
Crowded, hot Regrets about what
Quantitative Methods (QBA) 25
Trang 26Example: Having a party outdoors with no rain is
i.e this is my maximum willingness to pay for it if it
Very pleasant party
1
100
1
Rain
Crowded but dry
Proper feeling of being sensible
50
g
No Rain
Crowded, hot Regrets about what
Quantitative Methods (QBA) 26
Trang 27Example: Having a party outdoors with rain is worth
i.e a hypothetical someone would have to pay me at
Very pleasant party
1
100
1
Rain
Crowded but dry
Proper feeling of being sensible
50
g
No Rain
Crowded, hot Regrets about what
Quantitative Methods (QBA) 27
Trang 28Very pleasant party
1
100
1
Rain
Crowded but dry
Proper feeling of being sensible
50
g
No Rain
Crowded, hot Regrets about what
Quantitative Methods (QBA) 28
Trang 29Very pleasant party
1
Rain
Crowded but dry
Proper feeling of being sensible g
No Rain
Crowded, hot Regrets about what might have been
Quantitative Methods (QBA) 29
Trang 30Very pleasant party
1
0.6
1
Rain
Crowded but dry
Proper feeling of being sensible g
No Rain
Crowded, hot Regrets about what might have been
Quantitative Methods (QBA) 30
Trang 31Very pleasant party
1
0.6
1
Rain
Crowded but dry
Proper feeling of being sensible
0.4
No Rain
Crowded, hot Regrets about what might have been
0.6
Quantitative Methods (QBA) 31
Trang 32Very pleasant party
1
100
1
Rain
Crowded but dry
Proper feeling of being sensible
50
g
No Rain
Crowded, hot Regrets about what
Quantitative Methods (QBA) 32
Trang 33Very pleasant party
Crowded but dry
Proper feeling of being sensible g
No Rain
Crowded, hot Regrets about what might have been
Quantitative Methods (QBA) 33
Trang 34Very pleasant party
Crowded but dry
Proper feeling of being sensible
50 0
50
g
No Rain
Crowded, hot Regrets about what
0
- 50
Quantitative Methods (QBA) 34
Trang 35Decision Tree
Partial Cashflows, Payoffs and Probabilities
Payoffs
Trang 37Solving a Decision Tree
Wh t i th b t d i i ?
What is the best decision?
Quantitative Methods (QBA) 37
Trang 38Solving a Decision Tree
Consider decision “Outdoors”
Quantitative Methods (QBA) 38
Trang 39Solving a Decision Tree
Consider decision “Outdoors”
Use Expected Value:
Probability(Rain) = 40% Value = -100
Probability(No Rain) = 60% Value = 100
Quantitative Methods (QBA) 39
Trang 40Solving a Decision Tree
Consider decision “Outdoors”
Use Expected Value:
Probability(Rain) = 40% Value = -100
Probability(No Rain) = 60% Value = 100
Expected or average value:
0.4×(-100) + 0.6×100 = 20
Quantitative Methods (QBA) 40
Trang 41Expected Value
• Event node with n mutually exclusive
• Event node with n mutually exclusive
events (exactly one of the events will
occur)
occur)
Quantitative Methods (QBA) 41
Trang 42Expected Value
• Event node with n mutually exclusive
• Event node with n mutually exclusive
events (exactly one of the events will
Trang 43Expected Value
• Event node with n mutually exclusive
• Event node with n mutually exclusive
events (exactly one of the events will
Trang 44Expected Value
• Event node with n mutually exclusive
• Event node with n mutually exclusive
events (exactly one of the events will
Trang 48Decision Tree
20
-10
= 0.4*50+0.6*(-50)
Trang 49Decision Tree
20
-10
Trang 50Decision Tree
20
-10
Trang 51EV(Outdoors) > EV(Indoors)
20
20
-10
Trang 52Decision Tree
0.4 Rain
-100 Unhappy Outdoors -100 -100
Trang 53Evaluation of Decision Tree
0.4 Rain
-100 Unhappy Outdoors -100 -100
0 20 0.6
No Rain
100 Pleasant
100 100 1
Trang 54E l ti f D i i T
Evaluation of Decision Tree
Roll back method: start at terminal nodes and
Roll back method: start at terminal nodes and
work from right to left
Compute Expected Value of Event Nodes
Choose Event Node with maximum (or
minimum) EV in Decision Nodes
The value of the tree is the EV in the root of the tree (if values are money it is called the
EMV or Expected Money Value)
Quantitative Methods (QBA) 54
Trang 55Exercise 1 1:
Exercise 1.1:
Investment in a new product?
• Investment costs €10 000Investment costs €10.000
• Market research
=> 60% success, €80.000 profit
40% failure, - €30.000 loss
• Investment cost not yet included in profit
Quantitative Methods (QBA) 55
Trang 56Exercise 1 1:
Exercise 1.1:
Investment in a new product?
0.6 Product is success
70000 Invest 80000 70000
Trang 57Exercise 1 1:
Exercise 1.1:
Investment in a new product?
0.6 Product is success
70000 Invest 80000 70000
Trang 58Exercise 1 1:
Exercise 1.1:
Investment in a new product?
0.6 Product is success
70000 Invest 80000 70000
Trang 59• Note that we have not yet discussed risk attitude!
with a 40% chance
0.6 Product is success
with a 40% chance
70000 Invest 80000 70000
-10000 10000 26000 26000 0.4 0.4
Product is failure
-40000
1 -30000 -40000 26000
Don't invest
0
Quantitative Methods (QBA) 59
0 0
Trang 60We will talk about risk attitude (risk averse – risk loving) when we discuss the concept of “utility”
0.6 Product is success
70000 Invest 80000 70000
-10000 10000 26000 26000 0.4 0.4
Product is failure
-40000
1 -30000 -40000 26000
Don't invest
0
Quantitative Methods (QBA) 60
0 0
Trang 61Implicit assumption in analysis below:
we are risk indifferent
0.6 Product is success
70000 Invest 80000 70000
-10000 10000 26000 26000 0.4 0.4
Product is failure
-40000
1 -30000 -40000 26000
Don't invest
0
Quantitative Methods (QBA) 61
0 0
Trang 62Possible Justifications:
(1) We are risk indifferent
(2) We make these kinds of decisions a lot
0.6 Product is success
( )
70000 Invest 80000 70000
-10000 10000 26000 26000 0.4 0.4
Product is failure
-40000
1 -30000 -40000 26000
Don't invest
0
Quantitative Methods (QBA) 62
0 0
Trang 63Multistage Decisions
Quantitative Methods (QBA) 63
Trang 64Multistage Decisions
Quantitative Methods (QBA) 64
Trang 65Multistage Decisions
• Multistage problem: involves sequence of
decision alternatives and outcomes
Quantitative Methods (QBA) 65
Trang 66Multistage Decisions - Example
development on cancer treatment
Quantitative Methods (QBA) 66
Trang 67Multistage Decisions - Example
development on cancer treatment
of €85 000?
of €85,000?
Quantitative Methods (QBA) 67
Trang 68Multistage Decisions - Example
development on cancer treatment
of €85 000?
of €85,000?
Quantitative Methods (QBA) 68
Trang 69Multistage Decisions - Example
prepare product 1,2 or 3?
Quantitative Methods (QBA) 69
Trang 70Multistage Decisions - Example
prepare product 1,2 or 3?
Quantitative Methods (QBA) 70
Trang 71Multistage Decisions - Example
prepare product 1,2 or 3?
be fully predicted
Quantitative Methods (QBA) 71
Trang 72Multistage Decisions - Example
prepare product 1,2 or 3?
be fully predicted
Quantitative Methods (QBA) 72
Trang 73Multistage Decisions - Example
prepare product 1,2 or 3?
be fully predicted
Quantitative Methods (QBA) 73
Trang 74Multistage Decisions - Example
Best Case Worst Case
Product Equipment
costs
R&D costs
ability
Prob-R&D costs
ability
Prob-Best Case Worst Case
Trang 75Multistage Decision Tree
Trang 76-5000
Trang 77-5000 + 85000
Trang 78-5000 + 85000 – 4000
Trang 79-5000 + 85000 – 4000 -60000
Trang 80-5000 + 85000 – 4000 -60000
= 16000
Trang 81Find best decision byFind best decision by roll back method
Trang 82Start at terminal nodes and work from right to left.
Compute expected value
of event nodes
Trang 83Start at terminal nodes
and work from right to
left
Trang 84Start at terminal nodes
and work from right to
left
Compute expected value
28000
of event nodes
Trang 85Start at terminal nodes
and work from right to
Trang 86Start at terminal nodes
and work from right to
Trang 87Choose event node with
maximum (or minimum)
maximum (or minimum)
EV in decision nodes
28000
29000
32000
Trang 88Choose event node with
maximum (or minimum)
maximum (or minimum)
EV in decision nodes
28000
29000
32000
Trang 89Choose event node with
maximum (or minimum)
maximum (or minimum)
Trang 90Next step: Again work
from right to left
Compute expected value
Trang 91Next step: Again work
from right to left
Compute expected value
= 13500
32000
Trang 92Next step: Again work
from right to left
Compute expected value
Trang 93Choose event node with
maximum (or minimum)
maximum (or minimum)
Trang 94Choose event node with
maximum (or minimum)
maximum (or minimum)
Trang 95Choose event node with
maximum (or minimum)
maximum (or minimum)
13500
Trang 96Sensitivity Analysis
• Sensitivity Analysis: how sensitive is the result for changes in
• Sensitivity Analysis: how sensitive is the result for changes in
values of parameters?
• Why is this an interesting question?
• Why is this an interesting question?
• E.g the probability to get the grant is usually a rough
estimation.
estimation
• We estimated it to be 0.50
• Do we get a complete different result if it is 0 49 or 0 51?
• Do we get a complete different result if it is 0.49 or 0.51?
Quantitative Methods (QBA) 96
Trang 97Sensitivity Analysis
S i h f hi i
Systematic approach of this question:
• We came to the conclusion that it makes sense to submit the proposal if chance to get it is 0 5
proposal if chance to get it is 0.5
• What is the minimum probability for which it still makes
sense to submit the proposal (possibly losing €5000)?
sense to submit the proposal (possibly losing €5000)?
Quantitative Methods (QBA) 97
Trang 980.6 High R&D
16000 Prepare product 1 -60000 16000
-4000 28000 0 4 -4000 28000 0.4
Low R&D
46000 -30000 46000
0.1 High R&D
Prepare product 3 -80000 -4000 -5000 13500
-4000 32000 0.9
Low R&D
36000 -40000 36000
Trang 990.6 High R&D
16000 Prepare product 1 -60000 16000
-4000 28000 0 4 -4000 28000 0.4
Low R&D
46000 -30000 46000
0.1 High R&D
Prepare product 3 -80000 -4000 -5000 13500
Trang 1000.6 High R&D
16000 Prepare product 1 -60000 16000
-4000 28000 0 4 -4000 28000 0.4
Low R&D
46000 -30000 46000
0.1 High R&D
p *32000+(1-p)*(-5000)
Prepare product 3 -80000 -4000 -5000 13500
Trang 1010.6 High R&D
16000 Prepare product 1 -60000 16000
-4000 28000 0 4 -4000 28000 0.4
Low R&D
46000 -30000 46000
0.1 High R&D
p *32000+(1-p)*(-5000)
Prepare product 3 -80000 -4000 -5000 13500
Trang 10237000*p=5000 p Divide both sides by 37000
=> p = 5/37 = 0 1351
Quantitative Methods (QBA) 102
> p 5/37 0.1351
Trang 103Sensitivity Analysis
Interpretation:
• For p = 0.1351, we are indifferent between submitting For p 0.1351, we are indifferent between submitting
the proposal or not since it gives us the EMV of zero in
Quantitative Methods (QBA) 103
not sensitive to small changes around 0.5.
Trang 104Value of Information
Quantitative Methods (QBA) 104
Trang 105Recall Dilemma: organize party
indoors or in garden?
Quantitative Methods (QBA) 105
Trang 106Recall Dilemma: organize party
indoors or in garden?
0.4 Rain
-100 Unhappy Outdoors -100 -100
0 20 0.6
No Rain
100 Pleasant
100 100 1