It's a (coarsened exact) match! Non-parametric imputation of European abstainers' vote

There is a long tradition of imputation studies looking at how abstainers would vote if they had to. This is crucial for democracies because when abstainers and voters have different preferences, the electoral outcome ceases to reflect the will of the people. In this paper, we apply a non-parametric method to revisit old evidence. We impute the vote of abstainers in 15 European countries using Coarsened Exact Matching (CEM). While traditional imputation methods rely on the choice of voters that are on average like abstainers, and simulate full turnout, CEM only imputes the vote of the abstainers that are similar to voters, and allows to simulate an electoral outcome under varying levels of turnout, including levels that credibly simulate compulsory voting. We find that higher turnout would benefit social democratic parties while imposing substantial losses to extreme left and green parties.