In almost all democratic national elections an individual vote matters only in highly unlikely situations. It can be said that it is more likely to win the jack pot of a national state lottery than to become once the decisive voter in a lifetime, or to be hit in a thunderstorm than to change the voting results. Thus, it can be said that individual voters generally cannot alter such an election result regardless of whether they vote or not and how they vote. The fact that nevertheless many individuals voluntarily participate in such elections suggests that people care about democracy as such.
In public choice theory it is assumed that individuals as voters act rationally, i.e., by their voting behavior they try to maximise their own benefits. The rational voter theory was first developed by Downs (1957), Tullock (1967), Riker and Ordeshook (1968), and it is summarized e.g., by Mueller (1989, Chap. 18), Struthers and Young (1989), and Schram (1991). Given the fact that voting means to invest some effort (gathering and evaluating information, going to the polling booth or asking for the ballot-papers for postal vote), the extremely low probability for one’s own vote being decisive makes voting apparently irrational. Because of this conclusion it is often asked why people vote, and many scholars have tried to give reasons in order to explain the discrepancy between the theoretical prediction and empirical observations refered to as "vote participation paradox."
According to public choice theory, voters’ decision to participate in a vote is driven by individual costs and benefits involved. The typical reason given by public choice theorists why benefits should be close to zero is the extremely low probability that the own vote is decisive (Mueller, 1989; Struthers and Young, 1989). Besides the low probability justification for not voting ("my vote won’t matter"), the costs of voting offer another justification. These costs include the necessary preparations (one needs the voting card or, as in the United States, is not even registered automatically by the authorities but has to take the initiative oneself) as well as the costs of information, i.e., in the case at hand the costs of making up one’s mind which party one should vote for. A clear-cut position about the support for one party or another is usually the result of gathering information and reevaluating, reinterpreting or even neglecting facts. By deciding not to vote, all these mental efforts can be avoided. Furthermore, important costs of voting are, of course, the opportunity costs in terms of lost working or leisure time.
The rational voter theory as applied in the literature on political support functions (for a survey see Nannestad and Paldam, 1994) somehow neglects the low probability argument for not voting and claims that people decide in public elections as in economic situations. In other words: a voter chooses that party or coalition whose program or expected policy is best for him or herself personally. According to such a view, parties are nothing more than competing firms trying to satisfy the voters’ demands (given a perfect competitive political system).
To justify such an approach one has to argue why the low probability-argument does not apply. One way would be that most voters’ subjective probabilities for being decisive are rather unrelated to the objective probabilities (for a discussion see Struthers and Young, 1989; a related argument referring to self-deception and diagnostic voting is given by Quattrone and Tversky, 1985). In the minimax-regret model of Ferejohn and Fiorina (1974) voting is interpreted as a decision under uncertainty, i.e., voters are unable to estimate the probabilities of the alternative outcomes and, consequently, neglect them by concentrating on the outcomes themselves.
The theory of low-cost decisions, on the other hand, is serious about the low-probability argument. Voting decisions are identified as situations where the individual decision is irrelevant for the individuals themselves and for all other individuals, though the collective decision is relevant for all individuals (Kirchgassner, 1992). The decision takes place behind a "veil of insignificance" (Kliemt, 1986) resulting in "wrong" decisions being without significant consequences for the decision-makers. One important aspect in this context is whether voters decide rationally between the alternatives, once they have decided to participate in the vote (Brennan and Buchanan, 1994 or Kliemt, 1986). The other dimension is to decide whether or not to vote. The theory of low-cost decisions suggests that because hard (economic) incentives are missing, soft incentives like those created by moral rules or psychic costs can exert a strong impact for such decisions. Consequently, the main difference between economic and voting decisions is that costs of following social (moral) rules are usually high in economic decisions but rather low in voting decisions.
As already Riker and Ordeshook (1968) argued, citizens may receive some utility from their act of voting independent of the outcome. Citizens may enjoy the act of voting because participating in democratic elections awakens political interests and thereby all the fun and inspirations induced by more or less active participation in political debates. Voters may also be concerned to maintain democracy (Downs, 1957) or derive some sort of satisfaction from complying with the ethic of voting or with "civic duty." According to this view, the rewards of voting are considered to be twofold: voting is not exclusively instrumental to determine the winning party or coalition, but also is a private consumption act from which benefits accrue independent of the outcome of the election. The distinction made is between the investment and consumption value of voting (e.g., Stigler, 1972 or Guttman et al., 1994) or between instrumental and expressive voting (Fiorina, 1976).
In empirical studies there is quite a lot of evidence that changes in the relevant variables, as e.g., in expected closeness, cause changes in the turnout rate (e.g., Kirchgassner and Schimmelpfennig, 1992). For an explanantion of the high turnout level, however, other variables turn out to be relevant like the sense of duty, inter- and intragroup relations or respondent’s level of political interest (see, for instance, Blais et al., 2000 for an empirical study conducted during the 1993 Canadian federal election campaign, or Schram and Sonnemans (1996) for evidence from a participation game experiment).
In an experiment Guth and Weck-Hannemann (1997) investigate the value of democratic voting rights by providing the participants the chance to sell them. More specifically, an incentive compatible mechanism was used to elicit the (willingness-to-accept) value of the voting right in the election of the German Bundestag in October, 1994. Moreover, a postexperimental questionnaire made it possible to assess the relative importance of answers to the question "why do people vote?"
The results are striking though consistent with observed turnout levels: Most of the participants did not want to sell their voting right even at the top price offered; only a small minority of participants would have sold their voting right for any positive price, i.e., only very few people view their individual voting power as inessential as suggested by the "why do people vote?" paradoxon; and another intermediate group was willing to sell their voting right for substantial prices, but refused to do so at very low prices.
The bids which, from a normative point of view, should reveal the true values for one’s voting right thus show a strong non-willingness to sell one’s voting right. Furthermore, the group of voters who hardly assign any positive value to their voting right is close to being negligible. Among the reasons why to vote most subjects viewed voting as a civic duty or as a possibility to state one’s opinion as the most important for their own decision.
In total, one may conclude (following Blais, 2000 as well as Kirchgassner and Pommerehne, 1993) that the rational choice model of voter participation is useful, but only in explaining behavior at the margins of social norms and other-regarding behavior, and that the importance and impact of low-cost decisions have to be fully recognized and more carefully studied in the future in public choice analysis.