Discouraged by the choice: A revision of the impact of information overload on voter turnout

The relationship between party system fragmentation and voter turnout is a long-studied phenomenon whose form has not yet been precisely defined. Some studies attribute the negative effects on turnout to the inability of voters to sufficiently influence government formation in fragmented party systems (Blais & Carty, 1990; Grofman & Selb, 2010; Jackman 1987; Norris 2002). Other authors point to the information intensity of electoral decision-making in the context of a large number of running parties (Cunow et al., 2023; Geys & Heyndels, 2010; Kostadinova, 2003; Taagepera 2014). However, these findings are inconsistent with the findings of meta-analyses that suggest that the relationship between the number of parties and turnout is not as strong as it might first appear (Cancela & Geys, 2016; Smets & Ham, 2013; Stockemer, 2017). The main objective of this research is to propose an alternative research approach to investigate the possible negative impact of party system fragmentation on voter turnout based on cognitive psychology and information overload assumptions (Malhotra, 1982; Miller, 1956; Payne, 1976; Simon, 1957; Simon, 1974). In examining the decision-making process, it is necessary to consider not just the effect of the number of options, but also the number of attributes of each option (Fasolo, McClelland, 2007; Malhotra, 1982; Scheibehenne, Greifeneder & Kleber, 2010) and the degree of mutual similarity of the presented options (Belabbes, 2023; Carmeci & Misuraca, 2009; Fasolo, et al, 2009; Shugan, 1980; Böckenholt et al., 1991), all of which can negatively affect the voter's decision-making process. The answer to the question of the possible mutual influence of the variables described above on voter turnout will be examined using data from parliamentary elections in European democracies. Besides the European Social Survey to estimate the voter turnout at the individual level, and the effective number of electoral parties (Casal Bértoa, 2023), the Manifesto Project Database will be utilized for the index of the effective number of issues in the electoral programs (Greene 2015), which reflects the number of issues on which each party placed the most emphasis in the elections in question. In this respect, the index would serve to quantify the number of attributes that voters are confronted with. Assessing the impact of the degree of similarity between the options, a second indicator linked to the above database, the Jaccard Similarity Index (Sanger & Warin, 2019), will be used to capture the degree of congruence, or polarization, between the electoral programs. This innovative approach to investigating the impact of party system fragmentation on voter turnout more accurately reflects the assumptions associated with the phenomenon of information overload, and thus allows the reality that voters are confronted with to be studied more precisely than has been the case to date.