Multi-Criteria Decision Aide (MCDA) at the Watershed Scale

1
Multi-Criteria Decision Aide (MCDA) at the
Watershed Scale
2
Decisions at the watershed scale are
characterized by
Multiple goals ? Multiple alternatives to meet
goals ? Multiple criteria for alternatives
? Multiple metrics, scale, and time dimensions of
criteria ? Multiple decision-makers with .
. . ? Diverse preferences All within a
decision environment where the only thing that is
certain is CHANGE. How can we structure such
a decision-making process?
3
At the watershed scale, what is the decision to
make?
GOAL

• Examples
• Quantitative growth oriented goals
• Qualitative development oriented goals
• Specific management or action plans

4
What are the decision alternatives that could
help reach that goal?

• Examples
• Business as usual
• Directed growth policies technical fixes
• Steady state

5
How do we choose amongst alternatives? What
criteria?

• Examples
• Economic (CEc) Employment, income, tax base
• Social (CSc) Income distribution, landscape
  character
• Environmental (CEv) Impervious surface, IBIs

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How do we evaluate these criteria?
Metrics Quantitative, qualitative
Degree of uncertainty Data
availability
Scale Stream site, tax parcel, neighborhood,
sub-catchment, township, catchment,
county, state . . .
Time Stream flow, industry and household
processes, land-use change, policy
change, economic change, government
change . . .
7
How do we arrive at a goal when multiple
perspectives are involved?

• Examples
• Equity weights
• Alliances and consensus building
• Group process design

8
How do we identify decision-makers preferences
withinand between each criterion?
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• Within each criterion
• Maximize or minimize
• Absolute or relative preference

10

• Within each criterion
• Degree of indifference threshold

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• Within each criterion
• Degree of indifference threshold
• Degree of preference threshold

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• Within each criterion
• Degree of indifference threshold, AND
• Degree of preference threshold

13

• Between criteria
• Weights

w1 w2 w3 1
14
Outcomes of the MCDA decision process

• Performance of each alternative by multiple
  criteria

C1
1
C4
C6
0
C2
C5
-1
C3
C7
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Outcomes of the MCDA decision process

• Pairwise comparison of alternatives by multiple
  criteria

Alt-1
Alt-2
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Outcomes of the MCDA decision process

• Preference ordering of alternatives for each
  individual, and the group as a whole

A2
A3
A1
A5
Partial
A4
A3
A4
A2
A1
A5
Complete
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Outcomes of the MCDA decision process

• Simultaneous comparison of criteria and
  alternatives (individual GAIA Plane)

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Outcomes of the MCDA decision process

• Simultaneous comparison of decision-makers and
  alternatives (group GAIA Plane)

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Outcomes of the MCDA decision process

• Sensitivity analysis walking weights and
  stability intervals

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Outcomes of the MCDA decision process

• Shared understanding
• Coalition and/or consensus building
• Concrete problem definition
• Visualization of points and strength of conflict
• Ample opportunities for revision
• AND
• Ranking of decision alternatives