Introduction

In the foregoing chapters, we have developed a theory of electoral preference which exploits the fact that electoral “choice” by a single individual is intrinsically nondecisive. For expositional purposes we have at times talked as if the probability of being decisive in large-number electorates is quite negligible. Nevertheless, in the fomulation of our central proposition (Proposition 1 in Chapter 2) we were careful to emphasize that the underlying logic does not depend on the particular value of the probability of being decisive, given only that that value is significantly less than one. Clearly, however, the probability of being decisive is an important parameter in the whole argument, and it is therefore important for us to devote some attention to its value. Interestingly, this is a matter on which there is some disagreement. Some writers claim that, under most reasonable assumptions, the probability of being decisive is virtually infinitesimal (see, e.g., Meehl, 1977). Others, such as Beck (1975), argue that it is, though small, by no means negligible. And yet others – most conspicuously Palfrey and Rosenthal (1983) – claim that it may be remarkably high, and certainly large enough to provide an interest-based explanation of the turnouts that are actually observed in Western democratic experience.