Making a difference – not!

What is the probability your vote will make a difference?

Andrew GelmanNate SilverAaron Edlin

NBER Working Paper No. 15220
Issued in August 2009
NBER Program(s):   LE PE


One of the motivations for voting is that one vote can make a difference. In a presidential election, the probability that your vote is decisive is equal to the probability that your state is necessary for an electoral college win, times the probability the vote in your state is tied in that event. We computed these probabilities a week before the 2008 presidential election, using state-by-state election forecasts based on the latest polls. The states where a single vote was most likely to matter are New Mexico, Virginia, New Hampshire, and Colorado, where your vote had an approximate 1 in 10 million chance of determining the national election outcome. On average, a voter in America had a 1 in 60 million chance of being decisive in the presidential election.

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14 years ago

The same argument equally applies — what difference does your bit of pollution make? What difference does your little bit of corruption make? What difference does your little bit of theft make? or whatever.

I’m not the straw that broke the camel’s back, therefore I had nothing to do with the outcome.

I think the only logically consistent way to look at it, is that everyone takes the action that they see as “most correct” under the presumption that other people also will act in the way that they in turn see as correct. People should not vote in the hope that their particular vote might have special importance, they should vote because the alternative systems of power transfer involve coups, political cleansing and blood in the street. Keeping the Democratic system operational is an end in itself, regardless of who wins.