A lot of prestige is attached to getting a final poll right, because it is the one time when it is easiest to look at the actual results and work out which pollster was correct. But in a way, it’s a bit silly, because the last poll is the easiest one to get right, because it is the one where the most other polls are available to enable fine-tuning of assumptions.
Overall, the final Newspoll primary and 2PP poll was extremely accurate; AMR, Galaxy, ReachTEL, Morgan and Nielsen were all good to varying degrees, Morgan had a brilliant 2PP off mediocre primaries, Essential’s result was just plain mediocre, and the Lonergan mobile-only exercise was an interesting experiment but predictively a disaster.
Here, the much-lampooned Essential actually came up with the least skewed average in this period, although Galaxy was also very close to neutral. But while Galaxy tracked the aggregate with uncanny precision, Essential was one of the worst pollsters in terms of average error and average cumulative three-poll error. To say that it was accurate because it was unbiased on average is a little bit like saying that a clock stopped at midday displays the time more accurately across a 24-hour period than one that is ten minutes slow.
Every pollster that polled seat or local polls favoured the Coalition on average, and 2PP drift to the Coalition between when the polls were taken and the election made a lot of the seat polls look better than they actually were. On the whole, seat polls at this election were around 3.7 points too friendly to the Coalition at the time they were taken. The average actual difference from the seat polls to the election results, of 2.3 points, flatters them.
Read more, comment here: http://kevinbonham.blogspot.com.au/2013/11/2013-federal-election-best-and-worst.html
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