Election Polling and Late Swings in Vote Intentions

Polls in the first round of Brazil's 2022 presidential election diverged from the official results, leading to criticisms that they made mistakes. This paper examines an alternative explanation: that actual changes in vote intentions occurred between the polls and election day. Although unpopul...

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Detalles Bibliográficos
Autores: Pereira, Frederico Batista, Nunes, Felipe
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2024
País:Brasil
Institución:Universidade Estadual de Campinas (UNICAMP)
Repositorio:Opinião Pública (Online)
Idioma:portugués
OAI Identifier:oai:ojs.periodicos.sbu.unicamp.br:article/8676870
Acceso en línea:https://periodicos.sbu.unicamp.br/ojs/index.php/op/article/view/8676870
Access Level:acceso abierto
Palabra clave:Elections
Voting
Polling
Strategic voting
Undecided voters
Eleições
Voto
Pesquisas eleitorais
Voto estratégico
Indecisão
Elecciones
Encuestas electorales
Votantes indecisos
Descripción
Sumario:Polls in the first round of Brazil's 2022 presidential election diverged from the official results, leading to criticisms that they made mistakes. This paper examines an alternative explanation: that actual changes in vote intentions occurred between the polls and election day. Although unpopular, this explanation finds theoretical support in the scholarship based on two main processes: strategic voting and delayed decision-making. Using an experiment conducted a week before the election, we show how undecided voters and voters for less competitive candidacies displayed high propensity to change their minds after watching campaign videos. We also use data from one of the last polls conducted before the election to develop models that identify voters most prone to late swings in vote choice and reallocate such votes to adjust vote estimates. The results suggest that late swings in vote intentions can be a more than plausible phenomenon in recent Brazilian elections.