Wednesday, November 6, 2013

Virginia Governor's race 2013:
Post-mortem

Last night, the votes were tallied in the Virginia governor's race. The final result was

McAuliffe (Democratic) 48.0%
Cuccinelli (Republican) 45.5%
Sarvis (Libertarian) 6.6%

If you add these numbers together, you get 100.1%, which both means rounding error and effectively there were no votes for other candidates.

My system gave McAuliffe a 99.4% Confidence of Victory(CoV). That usually points to an easy win, but this was not easy, contested well into the night. What went wrong?

Well, my system does not promise to give the margin of victory, just who will win, so this one goes into the books as a win. The most recent polls that gave us the 99.4% was from Christopher Newport University, which had these numbers for the three candidates.

McAuliffe (Democratic) 45%
Cuccinelli (Republican) 38%
Sarvis (Libertarian) 10%

Notice that these numbers add up to 93%, so scaling up to make the three add up to 100.1% and keep their relative sizes, we get

McAuliffe (Democratic) 48.4%
Cuccinelli (Republican) 40.9%
Sarvis (Libertarian) 10.8%

The prediction for McAuliffe is very close, but Cuccinelli is quite low and Sarvis is very high. This is where almost all the error lies in the median poll. There was an outlier poll in the lastweek by Emerson College that had the lead at only 2% (very close to the truth), but their numbers for the three candidates are actually not very close.

McAuliffe (Democratic) 42%
Cuccinelli (Republican) 40%
Sarvis (Libertarian) 13%

This adds up to 95%, so scaling things up we get

McAuliffe (Democratic) 44.2%
Cuccinelli (Republican) 42.1%
Sarvis (Libertarian) 13.7%

This one isn't close to any of the true totals, only to the true margin of victory.

Quite simply, all the polls had the same problem. People lied about voting for the Libertarian.


As Republicans stake out a weird space (we want a government small enough to fit into your bedrooms and glove compartments) some people on the right have taken to calling themselves "Libertarians".

My problem with this is simple enough. I was registered Libertarian in 1976.

And then I met some of them.

I heard so many arguments that one nightmarish evening. Then, they were considered fringe and unacceptable but now, the same ideas are repeated across the Internet and in some circles considered mainstream. Here are a few.

a) Social Security can't survive.

b) The Post Office is an intolerable obstruction to liberty.

c) Government should have nothing to do with education.

d) Taxation is theft.

e) You should be able to smoke pot.

Well, I agree with one of those positions.

I want to keep my system as simple and clean as possible, but I have find a way to factor in what a significant but hopeless third party candidate really means. A Libertarian vote does not have an equal chance to go Democratic or Republican or stay home if the option to vote Libertarian is removed.

Since all my system promises is to call the winner sometime during the last week, last night counts as a win. As the old baseball saying goes, every hit looks like a line drive in the box score. But the next time a Libertarian appears be drawing a large number for a third party, my system has to come up with a method for adjusting the Confidence of Victory.

It is said you only learn from your mistakes. I got the winner this time, but it was still a mistake. We will see how much I learn from it.


2 comments: