Human Settlements Review - Parliamentary Monitoring Group

ij
ij
max
j
Human Settlements Review, Volume 1, Number 1, 2010
4.3 The proposed assessment
method
The proposed framework presents a multicriteria
optimisation problem. There are many
techniques for multi-criteria optimisation, such
as simple multi-attribute rating techniques, the
analytical hierarchy process, order preference
by similarity to ideal solution (Engelbrecht,
2007: 113-177). The simple additive weighting
(SAW), one of the simplest and probably the
best known and most widely used technique, is
recommended in this study. The model is used
to aggregate the scores into one score based
on the criteria weights. At first the scores are
normalised (converted) by the formulas:
1.
x
ij
a
=
a
ij
max
j
ij
2. xij
=
max
a j
Where
aij
xij
= = the score for the criterion.
max
a j
When the criteria are maximised, Formula 1
has to be used, and Formula 2 when the criteria
are minimised. The scores are aggregated into
one score using the formula:
3.
aij
xij
=
max
a j
a
Where
x =
a
is the total score, is the number
aij
xij
=
max
of criterion, a j
s the weight of each criterion,
and is the normalised score of the criterion.
In the event that the criteria are not measurable,
it is proposed to approach several stakeholders,
including academics and industry players to
rate the technology. However, it is important
a
to note that such score rating is subjective and
based on the perceptions of the respondents.
Yet, statistically the information can be used to
draw objective conclusions. Alternatively, it is
proposed that such criteria be defined in terms
that can be quantified and systems developed
to capture data which can then be presented
and analysed accordingly.
It is also necessary to compute the weighting
of the three pillars of sustainability (socioeconomic,
technical and environmental). Such
computation can be based on a field survey
where the targeted community participates
to establish the most pressing issues, which
can then be weighted using social science
techniques. The score rating for each criterion
and category (technical, socio-economic and
environmental) can be averaged, normalised
and aggregated into one score. The grand
total score rating can then be calculated as the
sum of the three total scores.
6 Conclusions and
recommendations
The concept of sustainable development is
now well defined and it can be applied to any
sphere of development and decision making,
including the built environment. The proposed
framework defines building technologies
responsive to the urban poor in terms of
technical, socio-economic and environmental
sustainability objectives in the regional context.
Building construction technologies can be
analysed, evaluated and finally compared in
order to select the optimal variant according to
the given set of criteria. The outcome of such
an evaluation can enhance the understanding
of the potentials of the technologies,
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