This process
also sought to confirm that sampling sites targeted a range of bays
expected to have high to low pollution levels. Expert opinion is
widely used as evidence across many disciplines (see Cooke,
1991; Alho, 1997; Liao, 2005), especially where the variable of
interest is dependent on multiple and complex inter-related causal
factors and hence uncertainty is high in terms of the relative contribution
of probable causal factors.