Do Polls Influence the Vote?
https://www.press.umich.edu/pdf/0472099213-ch11.pdf
https://www.france24.com/en/20170506-france-media-rules-prohibit-election-coverage-over-weekend-presidential-poll
“Starting from the night before polls open, it is illegal to publish or broadcast by all means of communication any message that may be categorised as electoral propaganda,” France’s Superior Audiovisual Council, or CSA, said in a statement. France prohibits polling 44 hours before presidential and legislative elections, likely to prevent the effect of information cascades that might influence election results. However, do polls really influence the vote?
First, we discuss what an information cascade is. An information cascade develops when people abandon their own information in favor of inferences based on earlier people’s actions. Individuals in a cascade are imitating the behavior of others, drawing rational inferences from limited information. In the case of polling, polls indicate how well parties are doing in an election and allow voters to see which party is in the lead. After seeing the results of the polls, voters may feel inclined to match their vote to the vote of the majority of the population.
How does this work? Let’s say you are a voter in an election. Based on your own research and values, you vote for party A. However, when the results of the polls come out, you see that most people voted for party B. If you believe that other voters have similar values to you, it might be rational to join the crowd at B rather than to follow your own information.
So the question is, does this actually happen? According to the University of Michigan study, this social process does occur in election polling. Information provided by polls affects voters’ perceptions and changes their expectations about the outcome of the election. France’s period of prohibition on election polling seems justified.