The decision to accept or to reject an empirical hypothesis concerning the risks and hazards of a pesticide requires assessing the cost's of error if the wrong decision is taken. The assessment of such costs involves scientists in problems which are closely related to those which policy‐makers face in deciding what to do in view of the information provided by scientists. These problems include the unforeseeable effects of agricultural technologies, the assessments of costs and benefits, and the choice of decision (...) rule to use in policy formation. I conclude that the combined impact of these problems motivates the use of prudentially weighted decision rules in forming policies which regulate the use of pesticides, and it motivates the development of bio‐environmental alternatives to chemically based pest control policies. (shrink)

Arrow's Independence of Irrelevant Alternatives (IIA) has been under criticism for decades for not taking account of preference intensities. Computer-simulation results by Aki Lehtinen concerning strategic voting under various voting rules show that this intensity argument does not need to rest on mere intuition. Voters may express intensities by voting strategically, and that this has beneficial aggregate-level consequences: utilitarian efficiency is higher if voters engage in strategic behaviour than if they always vote sincerely. Strategic voting is thus unambiguously beneficial under (...) a utilitarian evaluation of outcomes. What has been considered the main argument for IIA turns out to be one against it. This paper assesses the implications of these results for interpretations of Arrow's theorem and the Gibbard-Satterthwaite theorem in a discussion on the methodological and philosophical arguments concerning preference intensities and IIA. (shrink)