Perceptual learning

Unit 2 Approaches to Decision Analysis Unit 3 Types of Decision Situations Unit 4 Decision Trees

UNIT 1 ELEMENTS OF DECISION ANALYSIS

CONTENTS 1.0 Introduction 2.0 Objectives 3.0 Main Content

3.1 What is a Decision?

3.2 Who is a Decision Maker?

3.3 Decision Analysis

3.4 Components of Decision Making 3.4.1 Decision Alternatives 3.4.2 States of Nature 3.4.3 The Decision

3.4.4 Decision Screening Criteria 3.5 Phases of Decision Analysis

3.6 Errors that can Occur in Decision Making 4.0 Conclusion

5.0 Summary

6.0 Tutor-Marked Assignment 7.0 References/Further Reading 1.0 INTRODUCTION

Business Decision Analysis is the discipline comprising the philosophy, theory, methodology, and professional practice necessary to address important decisions in a formal manner. Decision analysis includes many procedures, methods, and tools for identifying, clearly representing, and formally assessing important aspects of a decision, for prescribing a recommended course of action by applying the maximum expected utility action axiom to a well-formed representation of the decision, and for translating the formal representation of a decision and its corresponding recommendation into insight for the decision maker and other stakeholders.

2.0 OBJECTIVES

At the end of this unit, you should be able to:

 define a decision

 define a decision maker

 describe the components of decision making

 outline the structure of a decision problem.

3.0 MAIN CONTENT

3.1 What is a Decision?

A decision can be defined as an action to be selected according to some pre-specified rule or strategy, out of several available alternatives, to facilitate a future course of action. This definition suggests that there are several alternative courses of action available, which cannot be pursued at the same time. Therefore, it is imperative to choose the best alternative base on some specified rule or strategy.

3.2 Who is a Decision Maker?

A decision maker is one who takes decision. It could be an individual or a group of individuals. It is expected that a good decision maker should be skilled in art of making decisions.

3.3 Decision Analysis

Decision making is a very important and necessary aspect of every human endeavour. In life, we are faced with decision problems in everything we do. Individuals make decisions daily on what to do, what to wear, what to eat etc. Every human being is assumed to be a rational decision maker who takes decisions to improve his/her wellbeing. In business, management have to make decision on daily bases on ways to improve business performance. But unlike individual decision making, organisational or business decision making is a very complex process considering the various factors involved. It is easy to take decision for simple situation but when it gets complex, it is better not to rely on intuition. Decision theory proves useful when it comes to issues of risk and uncertainty (Adebayo, et al. 2010).

3.4 Components of Decision Making

Earlier, we stated that complex decision problem involve risk and an uncertainty and as such, certain logic, rules, procedures should be

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applied when analysing such situation. The major components that constitute risk and uncertainty in decision making are:

 Decision alternatives

 States of nature

 The decision itself

 Decision screening criteria.

We now briefly discourse each of these components.

3.4.1 Decision Alternatives

These are alternative courses of action available to the decision maker.

The alternatives should be feasible, and evaluating them will depend on the availability of a well-defined objective. Alternative courses of action may also be seen as strategies or options from which the decision maker must choose from. It is due to the existence of several alternatives that the decision problem arises. If there were only one course of action, then there will be no decision problem.

Alternatives present themselves as:

(a) Choices of products to manufacture (b) Transportation routes to be taken (c) Choice of customer to serve

(d) Financing option for a new project (e) How to order job into machines, etc.

3.4.2 States of Nature

A state of nature is a future occurrence for which the decision maker has no control over. All the time a decision is made, the decision maker is not certain which states of nature will occur in future, and he has no influence over them (Taylor III, 2007). For instance, if a company has a contract to construct a 30km road, it may complete the construction of the full stretch of road in six months in line with a laid down plan. But this plan will be hinged on the possibility that it does not rain in the next six months. However, if there is consistent heavy rain for the first three months, it may delay the progress of work significantly and as a result, prolong the completion date of the project. But if actually there is no occurrence of heavy rainfall, the company is likely to complete the road as scheduled.

3.4.3 The Decision

The decision itself is a choice which is arrived at after considering all alternatives available given an assumed future state of nature. In the view of Dixon-Ogbechi (2001), “A good decision is one that is based on logic, considers all available data, and possible alternative and employs quantitative technique” she further noted that, occasionally, a good decision may yield a bad result, but if made properly, may result in successful outcome in the long run.

3.4.4 Decision Screening Criteria

In the section above, we mentioned that the decision itself is a choice which is arrived at after considering all other alternatives. Consideration of alternative courses of action is not done arbitrarily; it is done using some standardise logic or methodology, or criterion. These criteria form the basis upon which alternatives are compared. The strategy or alternative which is finally selected is the one associated with the most attractive outcome. The degree of attractiveness will depend on the objective of the decision maker and the criterion used for analysis (Ihemeje, 2002).

SELF-ASSESSMENT EXERCISE i. Define a decision.

ii. Who is a decision maker?

iii. What do you understand by states of nature?

iv. What is decision analysis?

v. List the two most prominent business objectives.

3.5 Phases of Decision Analysis

The process of analysing decision can be grouped into four phases.

These four phases from what is known as the decision analysis cycle.

They are presented as follows:

 Deterministic analysis phase: This phase accounts for certainties rather than uncertainties. Here, graphical and diagrammatic models like influence diagrams and flow charts can be translated into mathematical models.

Necessary tools are used for predicting consequences of alternatives and for evaluating decision alternatives.

 Probabilistic analysis: Probabilistic analyses cater for uncertainties in the decision making process. We can use the decision tree as a tool for probabilistic analysis.

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 Evaluation phase: At the phase, the alternative strategies are evaluated to enable one identify the decision outcomes that correspond to sequence of decisions and events.

3.6 Errors that can Occur in Decision Making

The following are possible errors to guide against when making decisions.

 Inability to identify and specify key objectives: Identifying specific objectives gives the decision maker a clear sense of direction.

 Focusing on the wrong problem: This could create distraction and will lead the decision maker to an inappropriate solution.

 Not giving adequate thoughts to trade-offs which may be highly essential to the decision making process.

4.0 CONCLUSION

Decision can be made either as single individuals or as group of individuals or as organisations. Those decisions are made in order to meet laid down goals and objectives which in most cases are aim to bring about improvement in fortunes.

5.0 SUMMARY

In this unit, the elements of decision analysis were discussed. It began with defining a decision, and who a decision maker is. Further, it considers the components of decision making, structure of a decision problem and finally errors that can occur in decision making. This unit provides us with concepts that will help us in understanding the subsequent units and modules.

6.0 TUTOR-MARKED ASSIGNMENT 1. Who is a decision maker?

2. Define decision analysis.

3. List and explain the components of decision.

7.0 REFERENCES/FURTHER READING

Ackoff, R. & Sisieni, M. (1991). Fundamentals of Operations Research.

New York: John Wiley and Sons Inc.

Adebayo, O.A., Ojo, O. & Obamire, J.K. (2006). Operations Research in Decision Analysis. Lagos: Pumark Nigeria Limited.

Churchman, C.W. et al. (1957). Introduction to Operations Research.

New York: John Wiley and Sons Inc.

Howard, A. (2004). “Speaking of Decisions: Precise Decision Language”. Decision Analysis, Vol. 1 No. 2, June.

Ihemeje, J.C. (2002). Fundamentals of Business Decision Analysis.

Ibadan: Sibon Books Limited.

Shamrma, J.K. (2009). Operations Research Theory & Application.

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UNIT 2 APPROACHES TO DECISION ANALYSIS