Introduction Of Decision Making
resources: Weighting Methods and their Efects on Multi-Criteria Decision Making Model Outcomes in Water Resources Management,
Tentative guidelines to help choosing an appropriate MCDA method
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Decision-Making Process [1]
Steps
1. Problem in hand is clearly defned.
2. Some other important requirements are then
listed on which the solution of multi-criteria model was dependent.
3. Objectives or goals of the multi-criteria problem are established.
4. deals with the establishment of alternatives which are going to be considered in a decision- making process with objective to choose the best alternative.
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5. Evaluation criteria are decided. The criteria should satisfy some previously fied standards.
For eiample, the chosen criterion may change its value in space and time.
6. The siith step of the process is very important as it involves the selection of an appropriate
multi-criteria decision making method for solving the problem in hand. Later the chosen MCDM
method is applied to the list of alternatives which was fnalized in Step 4 of the decision process
7. Later the chosen MCDM method is
applied to the list of alternatives which was fnalized in Step 4 of the decision process
8. Final step of the decision-making process is checking the results of the model and
performing sensitivity analysis test.
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multi-criteria decision making
Defne multi-criteria problem and objectives eiplicitly.
List and describe alternatives for meeting objectives or goals.
Defne criteria/attributes/performance indicators to measure performance of alternatives.
Carry out studies to gather data and evaluate criteria.
Prepare a decision matrii by arranging alternatives against criteria.
Elicit criteria subjective or objective weights for criteria.
Rank alternatives and communicate results with interest groups.
Decision-makers make decisions with input of interest group and get MCDM results.
began in 1971
The main objective of MCDM is to provide decision-makers with a tool in order to
enable them to advance in solving a multi- criteria decision problem, where several
conflicting criteria are taken into account
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Classifcation of MCDM
AHP: Analytic Hierarchy Process
ANP: Analytic Network Process
ELECTRE: Elimination Et Choii Traduisant la Realite (French)—
(Elimination and Choice Translating Reality) (English)
GP: Goal Programming
MACBETH: Measuring Attractiveness by a Categorical Based Evaluation Technique
MAUT: Multi-Attribute Utility Theory
MAVT: Multi-Attribute Value Theory
PROMETHEE: Preference Ranking Organization Method for Enrichment Evaluation
TOPSIS: Technique for Order Preference by Similarity to Ideal Solution
WSM: Weighted Sum Model
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Three categories of MCDM
Elementary
This proposes methods which alternate calculation steps, giving successive
compromising solutions, and dialog steps,
leading to an eitra source of information on
the decision-maker’s preferences
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Unique synthesis criterion approach
It consists of aggregating the diferent
points-of-view into a unique function which
will be optimized
Outranking synthesis approach
It consists in the development of a relationship called an outranking
relationship, which represents the decision- maker’s preferences, the relationship being eiplored in order to help the decision-
maker solve his/her problems
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Characteristics of MCDM
Not all MCDM methods are recommended for solving any multi-criteria decision problem.
Some MCDM methods can only take quantitative data to process with evaluation phase of the
decision-making and some can work with both types of data (quantitative and qualitative).
There are also some other characteristics of multicriteria decision-making methods, e.g.
transparency and cost
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How to Select an Appropriate MCDM Method [2]
There is no single MCDM method which can be superior method for all decision- making problems
Diferent MCDM methods will yield
diferent recommendations
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Guideline G1: Determine the stakeholders of the decision process. If there are many decision
makers (judges), one should think about group decision making methods or group decision
support systems (GDSS).
Guideline G2: Consider the DM `cognition' (DM way of thinking) when choosing a particular
preference elucidation mode. If he is more comfortable with pairwise comparisons, why using tradeofss and vice versa?
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Guideline G3: Determine the decision
problematic pursued by the DM. If the DM wants to get an alternatives ranking, then a ranking method is appropriate, and so on.
Guideline G4: Choose the MCAP that can handle properly the input information available and for which the DM can easily provide the required
information; the quality and the quantities of the information are major factors in the choice of the method.
Guideline G5: The compensation degree of the MCAP method is an important aspect to consider and to
eiplain to the DM. If he refuses any compensation, then many MCAP will not be considered.
Guideline G6: The fundamental hypothesis of the
method are to be met (veri®ed) otherwise one should choose another method
Guideline G7: The decision support system coming with the method is an important aspect to be considered
when the time comes to choose a MCDA method.
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The Role of Weights MCDM
Weights of criteria play an important role for measuring overall preferences of alternatives.
Because of having diferent aggregation rules, MCDM methods use these weights in diferent ways.
diferentvweighting methods have been developed to use them in diferent MCDM methods.
It is very importance that the decision-maker (DM) understands the true meaning of these weights
the interpretations of criteria
weights in MCDM
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Classifcation of Weighting Methods
Weights assigned to criteria in multi-criteria evaluation method is an important step as fnal results of the multi-criteria decision- making method largely depend on such weights
The simplest way to assign weights to criteria is ‘equal weights method’ that
distributes weights equally among all the
criteria
The main purpose of a weighting method is to attach cardinal or ordinal values to
diferent criteria to indicate their relative importance in a multi-criteria decision-
making method.
These values are then used by the MCDM method in subsequent evaluation of the
alternative
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A classifcation of weighting
methods
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Subjective Weighting Methods
Criteria weights are derived from the decision- maker’s judgment on criteria.
This means that the subjective methods are to
determine weights solely according to the preferences of decision makers.
Criteria weights determined by the subjective weighting methods reflect the subjective judgment of the decision- maker, but analytical results or rankings of alternatives based on the weights can be influenced by the decision maker due to his/her level of knowledge and eiperience in the relevant feld
Objective Weighting Methods
In the objective weighting methods, preferences of
decision maker on multiple criteria are not involved and the criteria weights are obtained from mathematical
algorithms or models.
The objective methods determine criteria weights by
solving mathematical models automatically without any consideration of the decision maker’s preferences.
Objective weighting methods determine criteria weights by making use of the mathematical models, but they neglect the subjective judgment information of the decision maker
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Popular subj weighting methods
Direct Rating
Ranking Method
Point Allocation
Pairwise Comparison
Ratio Method
Swing Method
Graphical Weighting
Delphi Method
Simple multi-attribute ranking technique (SMART)
SIMOS Method
Popular Obj Weighting Methods
Entropy method.
Criteria Importance Through Inter-criteria Correlation (CRITIC)
Mean Weight.
Standard Deviation.
Statistical Variance Procedure.
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Future Reading
[1] N. H. Zardari, K. Ahmed, S. M. Shirazi, and Z. B. Yusop, “Literature Review,” in
Weighting Methods and their Efects on Multi-Criteria
Decision Making Model Outcomes in Water
Resources Management
, Springer, 2015, pp. 7–67. [2] A. Guitouni and J.-M. Martel, “Tentative guidelines to help choosing an appropriate
MCDA method,” Eur. J. Oper. Res., vol. 109, no.
2, pp. 501–521, 1998.
