Thursday, 24 September 2015

Flag election data: Electoral Commission bleg

I wonder whether the Electoral Commission will keep and publish the data on vote preference orderings in the preferential flag ballot. There are 120 potential permutations on the 5 orderings, but ...rather more where there's ballot drop-off. Still, it shouldn't be unmanageable.

It would be really interesting to check whether there were major or minor cycles that went unrevealed, whether there was a Condorcet winner, whether the Condorcet winner was picked by the preference elimination routine, and whether different run-off options would have yielded different winners. Recall that a Condorcet winner would be the flag that beats each and every other flag in a head-to-head vote. If one exists (and it isn't necessary that one does exist), it is desirable that a selection mechanism select it. If there isn't one, all choices are kinda arbitrary anyway so no particular reason to prefer STV and top-of-order elimination over voting by veto or other mechanisms, but no particular reason to prefer the others either.

I've sent a note in to the Electoral Commission via their website asking that they keep the data and publish it. We'll see.

While we're at it, though, it does seem ... ridiculous ... that we'd be collecting all the preference data and then running an elimination routine without first checking for a Condorcet winner. STV doesn't necessarily pick the Condorcet winner, if there is one. It took me all of five minutes to come up with a preference ordering that failed to reveal one. Shouldn't that be the first stage check before running the preference ballot? The preference data needed for running STV is all you need to check for a Condorcet winner. The algorithm for checking wouldn't be all that hard.

Since we seem to be running all kinds of process changes under extreme urgency anyway, why not have one more process change and ask the Electoral Commission to start by looking for a Condorcet winner?

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