The For example, Plate 32 illustrates the effects of
combining three of the factors with trade-off and
one without. In this case, proximity to roads is given
a criterion weight of 0.45, proximity to the labour
force is given a weight of 0.12, and the slope factor
is given a weight of 0.43. These are combined using
a standard weighted linear combination. This result
is then combined with the distance from wildlife
reserve factor using a minimum operator. The
absence of trade-off in this last step is clear – the
distance from wildlife reserve factor dominates the
result until it no longer represents the limiting
factor. The effect is clearly similar to that of a
constraint, but lacks the crispness of a traditional
constraint. In effect, the minimum operator with a
fuzzy measure represents a form of soft constraint.
Soft constraints are particularly useful where a
specific boundary cannot be reasonably established.
Indeed, it might be argued that this is more
commonly appropriate than the artificial boundaries
of traditional constraints.