Geoscience Reference
In-Depth Information
After finalizing the selected spatial indicators, the hierarchical decision model
is then developed. The decision model of this study is broken up into three major
levels, namely goal, objective, and design criteria. Goal is the topmost level which
describes the decision problem. This study attempts to work out the most sus-
tainable urban development and therefore, the topmost level is to ''select the most
sustainable area''. The objectives of sustainability assessment comprise three
aspects: economic, environmental, and social. In order to identify the priorities of
three sustainable development objectives in the second level, and the relative
importance of different design criteria in the third level, a series of pairwise
comparisons have to be performed. The elements in both levels are then weighted.
By using pairwise comparisons, the relative importance of one criterion over
another can be expressed by ranking them using AHP's nine-point scale of
importance as shown in Tables
2
,
3
,
4
,
5
,
6
,
7
,
8
, and
9
.
The fractions are converted into decimals to acquire pairwise matrix. A short
computational way to obtain the ranking is to raise the pairwise matrix to powers
that are successively squared each time. The row sums are then calculated and
normalized.
i
;
j
¼ A
i
;
1
B
1
;
j
þ
A
i
;
2
B
2
;
j
þþ
A
i
;
n
B
n
;
j
¼
X
n
½
AB
A
i
;
r
B
r
;
j
ð
1
Þ
r¼1
From the computed eigenvector, the relative criteria are ranked as follows:
EcS
0.3761
The most important criterion
EnS
0.3341
The second most important criterion
ScS
0.2898
The least important criterion
The steps were then implemented for the next level which is design criteria
level where it includes all the spatial indicators from environment, economic and
social dimensions. Then, the criteria are ranked in a descending order from most
important to least important.
Economic sustainability indicators are represented by the numbers of integrated
terminals and stations for public transportations (TS), numbers of attraction areas
and recreational centres (TR) and percentage of grade 'A' business premises (GA).
TS
0.2380
The second most important criterion
TR
0.6254
The most important criterion
GA
0.1366
The least important criterion
Environmental sustainability indicators are represented by the percentage of
population living in areas prone to flooding (FA), provision of public open space
ratio compared to 1,000 population (OS) and percentage of centralized sewerage
(CS) (Tables
10
,
11
).
