Rational Abstention hurts Clinton

The results of the presidential election were on all accounts, shocking. Many of us, including myself, thought the race would not even be close. Leading up to the election, many polls such as FiveThirtyEight or the New York Times had Hillary's chances of winning the election between 70 and 90 percent. But to their dismay, Trump won the election and decisively at that. So what happened?

I would like to postulate that the polls who had Hillary winning the election so convincingly, actually contributed to her eventual loss. In the months leading up to the election, when undecided or relatively ambivalent voters saw that it was a forgone conclusion that Hillary would win, they became disinterested and complacent.

(1) If an individual voter concludes that the race is all but decided even before they vote, they are even further incentivized to abstain. Why should I take the time out of my day to go to the polls and vote if the outcome has already been decided? (2) Furthermore, the societal pressure applied by family members and friends is reduced when the election is expected to be a blowout. Conversely, in a tighter race there is more societal pressure applied to undecided voters and undecided voters are more likely to perceive their vote as potentially decisive.

Effects (1) and (2) can be explained by the rational abstention equation outlined in Mueller chapter 14 and Johnson's paper Voting, Rational Abstention and Rational Ignorance. The readings state that voters must satisfy the equation (p)*B + D > C in order to vote. The two forces mentioned above decrease the left side of the equation. Effect (1) decreases (p) and effect (2) decreases D. By decreasing the left side of the equation voters are further incentivized to abstain.

Because of these two forces, on-the-fence voters had increased incentives to abstain from voting. In turn this caused noticeably lower voter turnout - 55% ( the lowest in 20 years). In the end, those who abstained were in large part moderate voters who Hillary was counting on to win this election.