A paper entitled Information Flows, Expectation Formation, and Tactical Voting was presented at the ECPR General Conference 2013 at the Université de Bordeaux. It examines how results in the previous election (at constituency level) and parties' current popularity (as expressed in their performance in opinion polls) influence the formation of expectations about parties' chances at the constituency level and at the national level and how these expectations affect the intention to vote tactically.

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Development of the intention to vote tactically throughout the campaign to the election of the UK house of commons in 2010

The paper distinguishes two types of tactical voting: "wasted vote avoidance" (avoiding to vote for a candidate without a real chance to win the constituency seat) and "hung parliament avoidance" (avoiding to vote for a party whose success would make likely a 'hung parliament' without a single-party majority). It shows that hung parliament avoidance had some prevalence at the beginning of the 2010 electoral campaign, but that was in decline, especially after the first televised debate of the leaders of the Conservative, Labour and Liberal Democratic parties. It also shows that the loss to the Liberal Democrats to be expected from the intention to vote tactically declined throughout the campaign.

Vote intentions and counterfactual sincere vote intentions for the Liberal Democrats and the expected loss in vote share due to tactical voting.
Vote intentions and counterfactual sincere vote intentions for the Liberal Democrats and the expected loss in vote share due to tactical voting.