Data Science & Psychology Data Science applied to Values, Morals, Politics, & things that matter.

As a political junkie, I've been reading the spin on early voting with interest as each side talks about how they are using their ground game to get people to the polls.  Some have suggested that early voting doesn't matter as it simply gets those people who would have voted anyway to vote earlier.  That may or may not be true, but I believe that such analysis is missing one of the most important aspects of early voting.  Specifically, it creates a longer period for social influence to influence voter turnout.

One of the more interesting practical findings in social psychology is the finding that injunctive norms (e.g. telling people that they should vote) often do not work as well descriptive norms (e.g. telling people that everyone else voted).  In work made famous by Robert Cialdini, psychologists have found that telling people not to litter works quite badly if they perceive that litter is common.  This paradigm has been put to practical use in hotels which often tell you about the towel recycling behavior of other guests, rather than just asking you to recycle your towel.  The below graph shows the rate of towel recycling given injunctive vs. descriptive norms.

Does this principle apply to voting?  Absolutely!  Indeed, in the largest study I've ever seen, involving 61 million Facebook users, the Facebook data team successfully increased voting, verified by actual public voting data, by giving users the opportunity to see which of their friends had voted.  However, this occurred over a single day, where users had to login to facebook, report their voting, and have their friends see it in time to affect their behavior.  Imagine if social influence could occur over a period of days or weeks.  This is the true power of early voting.  It creates an environment where voting becomes the norm and who wants to be the person left out?  So even if early voting turnout efforts are bringing in people who would have voted anyway, it's likely that their behavior affects others.

Most polls show that the more people who vote, the more likely Obama will win this election, as polls of registered voters tend to show higher support for Obama than polls of likely voters, given that conservatives tend to vote more consistently.  Obama wants more people to vote.  As such, it makes sense that Obama's campaign would promote early voting as they need to create an environment where the normative thing to do is to vote.  Everybody is doing it and who wants to be the one left out.  In contrast, Republicans do better in low turnout elections since their supporters tend to be more consistent voters.  It is no accident that Democrats consistently want polls to be open longer, while Republicans often resist.  As such, it is questionable whether Republican efforts to get conservatives to vote early are useful, especially if the voters are people who would already vote anyway.  The effect of an environment where everyone is voting is likely to stimulate voting amongst groups that traditionally vote less often and lean Democratic (younger voters and hispanics).

For people who want to affect the vote, the task is clear.   If you are a Republican, it might pay to be more subdued about your voting, and share it only with those who you know agree with you.  If you are a Democrat, tell everyone you can about your vote to broaden the electorate, and take advantage of early voting to tell people that you voted over a longer period of time.

- Ravi Iyer

ps. I voted two days ago.  It felt good.