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This paper compares four weighting methods in multiattribute utility measurement: the ratio method, the swing weighting method, the tradeoff method and the pricing out method. 200 subjects used these methods to weight attributes for evaluating nuclear waste repository sites in the United States. The weighting methods were compared with respect to their internal consistency, convergent validity, and external validity. Internal consistency was measured by the degree to which ordinal and cardinal or ratio responses agreed within the same weighting method. Convergent validity was measured by the degree of agreement between the weights elicited with different methods. External validity was determined by the degree to which weights elicited in this experiment agreed with weights that were elicited with managers of the Department of Energy. In terms of internal consistency, the tradeoff method fared worst. In terms of convergent validity, the pricing out method turned out to be an outlier. In terms of external validity, the pricing out method showed the best results. While the ratio and swing methods are quite consistent and show a fair amount of convergent validity, their external validity problems cast doubt on their usefulness. The main recommendation for applications is to improve the internal consistency of the tradeoff method by careful interactive elicitation and to use it in conjunction with the pricing out method to enhance its external validity.tradeoffs, weights, multiattribute utility, nuclear waste disposal, decision analysis

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This study examined what lay people mean when they judge the "risk" of activities that involve the potential for accidental fatalities (e.g., hang gliding, living near a nuclear reactor). A sample of German and American students rated the "overall risk" of 14 such activities and provided 3 fatality estimates: the number of fatalities in an "average year," the individual yearly fkality probability (or odds), and the number of fatalities in a "disastrous accident." Subjects' fatality estimates were reasonably accurate and only moderately influenced by attitudes towards nuclear energy. Individual fatality probability correlated most highly with intuitive risk ratings. Disaster estimates correlated positively with risk ratings for those activities that had a low fatality probability and a relatively high disaster potential. Annual average fatality rates did not correlate with risk ratings at all. These findings were interpreted in terms of a two-dimensional cognitive structure. Subjective notions of risk were determined primarily by the personal chance of death; for some activities, "disaster potential" played a secondary role in shaping risk perception. ~