Multi-Criteria Analysis Flashcards
1
Q
What is the value of a multi criteria analysis?
A
- It helps to evaluate alternatives: solutions, scenarios, land use options, products etc.
- MCA works with criteria with different dimensions, so you do not have to convert indicators ( e.g. into monetary values), and you can consider criteria that are difficult to measure ( e.g. social or religious aspects)
- MCA is a tool that can help evaluate the relative importance of all criteria involved and reflect their importance in the final decision making process.
- Helps to reach consensus in a multi-disciplinary team or group of stakeholders
- Team members don’t have to agree on the relative importance of the criteria or the rankings of the alternatives, each member enters his/her own judgements and makes a distinct, identifiable contribution to a jointly reached conclusion.
- Helps to make the decision making process transparent
2
Q
What is MCA?
A
Multi-Criteria Analysis is a decision making tool, developed for a complex multi-criteria problems that include quantitative and/or qualitative aspects of the problem in the decision making process.
3
Q
What is the purpose of MCA in ESA?
A
- ESA involves the study of complex environmental problems by identifying and analysing causes, mechanisms, processes, impacts, and potential solutions.
- MCA is used to compare and rank alternatives taking into account and evaluating their respective consequences.
4
Q
What are the characteristics of MCA?
A
- Criteria have different dimensions, e.g. costs, deposition levels, area of damaged ecosystems
- Criteria may differ in weight, e.g. acidification may be considered a bigger problem than eutrophication
- Weights depend on ‘vision’, e.g. various people have various preferences
- Qualitative and quantitative information, e.g. opinions about environment versus quantitative emissions loads
5
Q
Describe a generic procedure for MCA?
A
- Establish the decision context:
- Identify the overall goal of decision making
- Identify (sub)objectives
- What would distinguish between a good solution and a bad one?
- Convert objectives to measurable (sub)criteria
- Once you have set a criteria try to group them ( e.g. costs, effect on the environment, socio-economic consequences, side-effects on the issues)
- Assess the criteria on:
- completeness
- redundancy
- operationally
- mutual independence of preference
- double counting
- size
- impacts over time
- Identify alternative options
- ‘Score’ options performance against criteria
- Assess the expected performance ( consequences) of each solution against each criterion. Result is -performance matrix. This can be done:
- Quantitatively, e.g. in monetary terms, number of accidents, increase of CO2 emission, etc.
- Qualitatively, e.g. in words ‘no significant impact’
- To keep in mind:
- Take care that the scores are comparable
- Use the same sense of direction: usually better performance means a higher score
- Use e.g. interval scales (0-100) or based on Likert scale 1-5
- Assess the expected performance ( consequences) of each solution against each criterion. Result is -performance matrix. This can be done:
- ‘Weight’ criteria
- Assign a weight ( value) to each of the criteria to reflect their relative importance
- reflects the subjective opinion of a group of experts, stakeholders or actors
- Combine the weights and scores for each option to derive an overall value
- Si = w1si1 + w2si2 + ….+ wnsin = sum(n; j =1) wjsij
- Examine the results: evaluate & rank options
- Sensitivity analysis
6
Q
What are the different methods to assign weights?
A
- Ranking: assigning each criterion a rank that reflects its perceived degree of importance relative to the decision being made. This criteria can then be ranked ( first, second, etc.)
- Rating: similar to ranking, but criteria are assigned “percentage scores” between 0 and 100, while the total scores for all criteria must add up to 100
7
Q
What are the two types of ranking?
A
- Ordinal ranking: each expert is asked to put the list of criteria in order of importance
- Regular ranking: assigns each criterion a rank depending on its perceived importance
8
Q
What are the advantages of rating?
A
It provides both ordinal ( order of importance) and cardinal ( difference in magnitude between two criteria) measure of importance