“…Pérez-Liñán (2001) finds that neither multipartism, unicameralism, electoral disproportionality, the type of electoral district (whether it is competitive or not), nor compulsory voting are significant predictors of voter turnout in presidential and legislative elections. On the contrary, the findings of Fornos et al (2004) suggest that turnout is determined primarily by unicameralism, compulsory voting, and concurrent elections, which have significant positive effects on turnout. Kostadinova and Power (2007) also find an effect of institutional variables on voter turnout in the region: unicameralism, disproportionality, district magnitude, and concurrent elections are all significant predictors of participation in legislative elections.…”