A widely accepted “picture” equation of the voting calculus, originated by Downs’ is R = PB – C where R is reward; B is the perceived differential in benefits offered the voter by the two parties; P is the probability that his vote will bring about the favored party’s victory; and C represents the costs incurred in the voting decision. The correspondence of the Downsian equation to the putative
decisional calculus of the prospective voter has been tested with a variety of methods. The data used are typically drawn from national election surveys. No two studies have operationalized the terms of the equation in the same way. Nevertheless, the calculus,
with various modifications, has been shown to have predictive utility. relative importance of the formula’s various terms. It is the contention of this paper that voting costs have been treated unrealistically and their importance relative to the other factors unduly discounted.
Source: The Journal of Politics 42.3 (Aug 1980): 854-863
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