Future-sketching and multi-attribute evaluation may affect your preferenceorder of complex policy scenarios

A total of 158 citizens from Groningen and surrounding villages evaluated s ummary descriptions of four different policy scenarios (A-D) for metropolit an traffic in the next decades. Eighty subjects rank-ordered the scenarios following a multi-attribute evaluation method. The other 78 subjects provid ed an 'intuitive' rank-ordering. Of each group, half of the subjects did an d the other half did not sketch their expected future consequences of each scenario. Multi-attribute evaluation of policy scenarios yielded a greater consensus among subjects and it led to another mean preference order than d id intuitive evaluation. Of all preference orderings, 138 (87%) could be un folded into one J(oint)-scale ranging from the 'alternative-friendly' scena rio D to the 'car-friendly' scenario A. Individual subjects' ideal points a nd corresponding individual preference orders fell into seven different cat egories along this J-scale. Subgroups holding the seven preference orders s ignificantly differed in traffic problem awareness, annual car-kilometrage and the percentage of multi-attribute evaluators. It is concluded that mult i-attribute evaluation of complex preference objects may guide subjects tow ards greater consensus and towards another preference ranking than when pol icy scenarios are evaluated intuitively. This may be mediated by the set of value attributes used, whose structure of intercorrelations may reflect (o r induce) a simple(r) preference foundation. The results are interpreted in terms of cognitive elaboration of choice alternatives which serves the con struction of preferences about them. The importance of good 'scenario think ing' for complex policy making is emphasized. (C) 1999 John Wiley & Sons, L td.