Rethinking Brownfield Redevelopment features:Fuzzy Delphi Method

Brano Glumac

Intro

• Two basic ways to extract the data• Database collected from final users

• Database collected from experts

PAGE 204/21/23

Method

• Delphi Method helps the group thinking process• From (Dalkey and Helmer, 1963)

• Procedure: Brainstorming, Narrowing Down, Ranking

PAGE 304/21/23

Research task

• What are the most important features for

Brownfield Redevelopment?

• Features

• Brownfield (Alker, 2000)

PAGE 404/21/23

Fuzzy Delphi

• What is it?• Derived from the traditional Delphi technique and Fuzzy

Set theory (Murray, Pipino, and Gigch 1985)

• Fuzziness lack of definite or sharp distinctions

• Benefits• Incorporate uncertainty due to human factor

• Less questionnaires

PAGE 504/21/23

PHASE 1Brain -storming

• experts as individuals not panelists

• features from the literature

• remove duplicates and unify terminology

• Questionnaire 1: Send consolidate list

to experts for validation

• refine final version

PHASE 2Ranking

• Questionnaire 2: Experts rate features

• calculate with Fuzzy Delphi Method

• final result is list of important features

Fuzzy Delphi Procedure

Fuzzy Delphi Calculation Steps

• Steps:

1. Validate features

2. Collect evaluation score for each feature

3. Set-up fuzzy number (Klir and Yuan, 1995)

4. Defuzzification S

5. Setting a threshold α

PAGE 704/21/23

Survey Results

Aspect Code - FeatureW = (a,b,c,d)

S Ranka b c d

Place A1 - Proximity 1,00 6,94 8,09 10,0 6,51 6

A2 - Accessibility 1,00 6,97 8,00 10,0 6,49 7

A3 - Usage 1,00 6,12 7,29 10,0 6,10 13

A4 - Embedded into the urban fabric 2,00 6,89 7,89 10,0 6,69 3

A5 - Contamination level 1,00 6,55 7,52 10,0 6,27 11

A6 - Skyline 1,00 4,03 5,53 10,0 5,14 21

A7 - Land Relief 1,00 3,34 4,46 10,0 4,70 22

A8 - Soil properties 1,00 4,89 5,97 10,0 5,46 20

A9 - Flora & Fauna 1,00 5,51 6,51 10,0 5,76 19

A10 - Heritage 1,00 6,50 7,50 10,0 6,25 12

A11 - Archeological site 1,00 5,83 7,00 10,0 5,96 18

A12 - Existing neighborhood image 1,00 5,91 7,03 10,0 5,99 17

Legal A13 - Ownership 1,00 6,73 7,85 10,0 6,39 9

A14 - Administrative support 4,00 7,54 8,63 10,0 7,54 2

A15 - Approval process 1,00 6,82 7,97 10,0 6,45 8

A16 - Support of local residents/users 1,00 6,69 7,80 10,0 6,37 10

A17 - Support of surrounding residents/users 2,00 6,77 7,74 10,0 6,63 4

Finance A18 - Governmental incentives 1,00 6,03 7,29 10,0 6,08 14

A19 - Potential for different land-use 3,00 8,29 9,17 10,0 7,61 1

A20 - Value capturing 1,00 6,03 7,17 10,0 6,05 15

A21 - Liquidation option 1,00 6,11 7,00 10,0 6,03 16

A22 - Current Real Estate Value 2,00 6,57 7,60 10,0 6,54 5

Survey Results

Overall Rating1 - A19 - Potential for different land-use - 7,612 - A14 - Administrative support - 7,54

Ratings of Independent developers1 - A14 - Administrative support - 8,202 - A4 - Embedded into the urban fabric - 8,023 - A2 - Accessibility - 7,754 - A19 - Potential for different land-use - 7,615 - A17 - Support of surrounding users - 7,506 - A12 - Existing neighborhood image - 7,397 - A15 - Approval process - 7,16

Rating Of Contractors1 - A19 - Potential for different land-use - 7,692 - A14 - Administrative support - 7,523 - A10 - Heritage - 7,234 - A13 - Ownership - 7,17

Rating of Governmental Agencies1 - A19 - Potential for different land-use - 7,962 - A14 - Administrative support - 7,333 - A2 - Accessibility - 7,214 - A10 - Heritage - 7,045 - A16 - Support of local users - 7,00

Discussion

• The selection procedure and importance of the Brownfield redevelopment features

• Different priorities for different expert groups