“…In general, we are unable to derive such conclusions from the collected survey data because the scale of questions in questionnaires is usually measured on an ordinal or nominal scale. Several statistical and intelligence methods have been applied to customer satisfaction analysis like conjoint analysis (Danaher, 1997), partial least squares (Ryan et al , 1999), targeted bootstrapping (Willson and Wragg, 2001) and artificial neural network approach (Hackl and Weslund, 2000). In recent years, we have seen increased attention being given to satisfaction analysis in the intelligence methods literature, where a simple description on how to model the customer retention problem using the Rough Sets (RS) model was given (Kowalczyk, 1997).…”