intro multi criteria

8/10/2019 Intro Multi Criteria

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Outline

Introduction and Background

Definitions

What is multi criteria evaluation?

How and when is it useful?

How does it work? Case study to show

how it is implemented Pros and cons of the method.

Why should we use it?


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Multi Criteria Analysis

Multi Criteria Decision Evaluation (MCDE)

Multi Criteria Preference Analysis

Multi Criteria Decision Making (MCDM)

Multi Objective Evaluation

These methods are essentially one and the

same!

MCDE= Multi-criteria decision evaluation is primarilyconcerned with how to combine the information from several

criteria to form a single index of evaluation


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Introduction

Engineering is a scarce resource:Identifying suitability for

Where to build a dam

Water flow

Mountainous?

Where to place a structure

Costs

Access

Greatest need

Criteria can be based on human or physical

geography factors


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History Background

Identifiying the Problems,

Constructing the Preferences,

Evaluating the Alternatives,

Determining the Best Alternatives.(Simon 1977; Keendy and Raiffa 1993; Kleindorfer,Kunreuther, and Schoemaker

1993)The historical origins of MADMcorrespondence between

Nicolas Bernoulli (1687

1759). Pierre Remond de Montmort(16781719), discussing the St. Petersburg paradox.


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Historical

Developmentof MADM


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Historical

Developmentof MODM


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DefinitionsDecisions: a choice between alternatives

Criterion: some basis for a decision. Two main classes:

Factor: enhancesor detractsfrom the suitability of a land

use alternative (e.g. distance from a road)

Constraint: limitsthe alternatives

Goal or target: some characteristic that the solution mustpossess (a positive constraint)


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The Basics


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What is it used for?

Decision making

Dispute resolution

Water resource management Sustainable development

etc


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Principles of MCDM

Methodology:

1. Determine criteria

(factors/constraints) to be included

2. Determining the weights for each

factor

3. Sensitivity analysis of results


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1stStep: Determine the

criteria to be included

Criteria determine the alternatives

Oversimplification of the decision problem couldlead to too few criteria being used

Using a large number of criteria reduces the

influence of any one criteria

Often proxies must be used since the criteria of

interest may not be determinable


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Example: Case study of asuitable dam and reservoir

siteCriteria used:RiverUrbanForestAccumulated water flowExisting reservoirWatershed boundaryCityHydraulic head

Undulation


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Determine the weights

A decision is the result of a comparison of one

or more alternatives with respect to one or more

criteria that we consider relevant for the task at

hand.

Among the relevant criteria we consider some as

more important and some as less important;

this is equivalent to assigning weights to the

criterion according to their relative importance.


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2nd stage, assigning weights


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Sensitivity analysis

sensitivity analysis: vary the

scores/weights of the factors to determine

the sensitivity of the solution to minor

changes

Choice of criteria (e.g. why included?)

Assesses the reliability of data: how stable is

the final result?

Choice for weighting factors is subjective

Will the overall solution change if you use

other weighing factors?


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MCDMGoods and Bads

Goods:

Dynamic problems

strongly simplified into a

linear modelStatic, lacks the time

dimension

Controversial method

too subjective?

Bads:

Gives a structured and

traceable analysis.

Possibility to use different

evaluation factors makes it

a good tool for discussion.

Copes with large amountsof information.

It works!


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intro multi criteria

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