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CHAPTER 4
Complexity of Decision Making
1
The Principle of Choice
2
What criteria to use? Best solution? Good enough solution?
Selection of a Principle of Choice
3
Not the choice phase
A decision regarding the acceptability of a solution approach
NormativeDescriptive
Normative Models
4
The chosen alternative is demonstrably the best of all (normally a good idea)
Optimization process
Normative decision theory based on rational decision makers
Rationality Assumptions
5
Humans are economic beings whose objective is to maximize the attainment of goals; that is, the decision maker is rational
In a given decision situation, all viable alternative courses of action and their consequences, or at least the probability and the values of the consequences, are known
Decision makers have an order or preference that enables them to rank the desirability of all consequences of the analysis
Suboptimization
6
Narrow the boundaries of a system
Consider a part of a complete system
Leads to (possibly very good, but) non-optimal solutions
Viable method
Descriptive Models
7
Describe things as they are, or as they are believed to be
Extremely useful in DSS for evaluating the consequences of decisions and scenarios
No guarantee a solution is optimal Often a solution will be good enough Simulation: Descriptive modeling technique
Descriptive Models
8
Information flowScenario analysisFinancial planningComplex inventory decisionsMarkov analysis (predictions)Environmental impact analysisSimulationWaiting line (queue) management
Satisficing (Good Enough)
9
Most human decision makers will settle for a good enough solution
Tradeoff: time and cost of searching for an optimum versus the value of obtaining one
Good enough or satisficing solution may meet a certain goal level is attained
(Simon, 1977)
Why Satisfice?Bounded Rationality (Simon)
10
Humans have a limited capacity for rational thinking Generally construct and analyze a simplified model Behavior to the simplified model may be rational But, the rational solution to the simplified model may
NOT BE rational in the real-world situation Rationality is bounded by
limitations on human processing capacitiesindividual differences
Bounded rationality: why many models are descriptive, not normative
Developing (Generating) Alternatives
11
In Optimization Models: Automatically by the Model!
Not Always So!
Issue: When to Stop?
Predicting the Outcome of Each Alternative
12
Must predict the future outcome of each proposed alternative
Consider what the decision maker knows (or believes) about the forecasted results
Classify Each Situation as UnderCertaintyRiskUncertainty
13
Decision Making Under Certainty
14
Assumes complete knowledge available (deterministic environment)
Example: U.S. Treasury bill investment
Typically for structured problems with short time horizons
Sometimes DSS approach is needed for certainty situations
Decision Making Under Risk (Risk Analysis)
15
Probabilistic or stochastic decision situation Must consider several possible outcomes for each
alternative, each with a probability Long-run probabilities of the occurrences of the given
outcomes are assumed known or estimated
Assess the (calculated) degree of risk associated with each alternative
Risk Analysis
16
Calculate the expected value of each alternative
Select the alternative with the best expected value
Example: poker game with some cards face up (7 card game - 2 down, 4 up, 1 down)
Decision Making Under Uncertainty
17
Several outcomes possible for each course of action BUT the decision maker does not know, or cannot
estimate the probability of occurrence
More difficult - insufficient information Assessing the decision maker's (and/or the
organizational) attitude toward risk Example: poker game with no cards face up (5 card stud
or draw)
Measuring Outcomes
18
Goal attainment Maximize profit Minimize cost Customer satisfaction level (minimize number of
complaints) Maximize quality or satisfaction ratings (surveys)
Scenarios
19
Useful in
Simulation What-if analysis
Importance of Scenarios in MSS
20
Help identify potential opportunities and/or problem areas
Provide flexibility in planning Identify leading edges of changes that management
should monitor Help validate major assumptions used in modeling Help check the sensitivity of proposed solutions to
changes in scenarios
Possible Scenarios
21
Worst possible (low demand, high cost) Best possible (high demand, high revenue, low cost) Most likely (median or average values) Many more
The scenario sets the stage for the analysis
22
The Choice Phase
23
The CRITICAL act - decision made here!
Search, evaluation, and recommending an appropriate solution to the model
Specific set of values for the decision variables in a selected alternative
The problem is considered solved only after the recommended solution to the model is successfully implemented
Search Approaches
24
Analytical Techniques
Algorithms (Optimization)
Blind and Heuristic Search Techniques
25
26
27
Evaluation: Multiple Goals, Sensitivity Analysis, What-If,
and Goal Seeking
28
Evaluation (with the search process) leads to a recommended solution
Multiple goals Complex systems have multiple goals
Some may conflict
Typically, quantitative models have a single goal
Can transform a multiple-goal problem into a single-goal problem
Common Methods
29
Utility theory Goal programming Expression of goals as constraints, using linear
programming Point system
Computerized models can support multiple goal decision making
Sensitivity Analysis
30
Change inputs or parameters, look at model results
Sensitivity analysis checks relationships
Types of Sensitivity Analyses
Automatic Trial and error
Trial and Error
31
Change input data and re-solve the problem
Better and better solutions can be discovered
How to do? Easy in spreadsheets (Excel)What-ifGoal seeking
Goal Seeking
32
Backward solution approach Example: Figure 2.10
What interest rate causes an the net present value of an investment to break even?
In a DSS the what-if and the goal-seeking options must be easy to perform
Goal Seeking
33
The Implementation Phase
34
There is nothing more difficult to carry out, nor more doubtful of success, nor more dangerous to handle, than to initiate a new order of things
(Machiavelli, 1500s)*** The Introduction of a Change ***
Important Issues Resistance to change Degree of top management support Users’ roles and involvement in system development Users’ training
How Decisions Are Supported
35
Specific MSS technologies relationship to the decision making process (see Figure 2.11)
Intelligence: DSS, ES, ANN, MIS, Data Mining, OLAP, EIS, GSS
Design and Choice: DSS, ES, GSS, Management Science, ANN
Implementation: DSS, ES, GSS
36
Alternative Decision Making Models
37
Paterson decision-making process Kotter’s process model Pound’s flow chart of managerial behavior Kepner-Tregoe rational decision-making approach Hammond, Kenney, and Raiffa smart choice method Cougar’s creative problem solving concept and model Pokras problem-solving methodology Bazerman’s anatomy of a decision Harrison’s interdisciplinary approaches Beach’s naturalistic decision theories
Naturalistic Decision Theories
38
Focus on how decisions are made, not how they should be made
Based on behavioral decision theory
Recognition models Narrative-based models
Recognition Models
39
Policy Recognition-primed decision model
Narrative-based Models (Descriptive)
Scenario model Story model Argument-driven action (ADA) model Incremental models Image theory
Other Important Decision- Making Issues
40
Personality types Gender Human cognition Decision styles
Personality (Temperament) Types
41
Strong relationship between personality and decision making
Type helps explain how to best attack a problem
Type indicates how to relate to other typesimportant for team building
Influences cognitive style and decision style http://www.humanmetrics.com/cgi-win/JTypes2.asp
Myers-Briggs Dimensions
42
Extraversion (E) to Intraversion (I) Sensation (S) to Intuition (N) Thinking (T) to Feeling (F) Perceiving (P) to Judging (J)
http://www.mypersonality.info/personality-types/
43
Gender
44
Sometimes empirical testing indicates gender differences in decision making
Results are overwhelmingly inconclusive
http://stumblingandmumbling.typepad.com/stumbling_and_mumbling/2009/08/gender-decisionmaking.html
http://www.ijpsy.com/volumen7/num3/176/factors-that-affect-decision-making-gender-EN.pdf
Cognition
45
Cognition: Activities by which an individual resolves differences between an internalized view of the environment and what actually exists in that same environment
Ability to perceive and understand information
Cognitive models are attempts to explain or understand various human cognitive processes
Cognitive Style
46
The subjective process through which individuals perceive, organize, and change information during the decision-making process
Often determines people's preference for human-machine interface
Impacts on preferences for qualitative versus quantitative analysis and preferences for decision-making aids
Affects the way a decision maker frames a problem
Cognitive Style Research
47
Impacts on the design of management information systems May be overemphasized
Analytic decision maker Heuristic decision maker
Decision Styles
48
The manner in which decision makers Think and react to problems Perceive their
Cognitive response Values and beliefs
Varies from individual to individual and from situation to situation
Decision making is a nonlinear process
The manner in which managers make decisions (and the way they interact with other people) describes their decision style
There are dozens
Some Decision Styles
49
Heuristic Analytic Autocratic Democratic Consultative (with individuals or groups) Combinations and variations
For successful decision-making support, an MSS must fit the Decision situation Decision style
50
should be flexible and adaptable to different usershave what-if and goal seeking have graphics have process flexibility
An MSS should help decision makers use and develop their own styles, skills, and knowledge
Different decision styles require different types of support
Major factor: individual or group decision maker
The system
51
Summary
52
Personality (temperament) influences decision making
Gender impacts on decision making are inconclusive
Human cognitive styles may influence human-machine interaction
Human decision styles need to be recognized in designing MSS