Tuesday, May 5, 2015

2015 Alberta provincial election projection

The following are ThreeHundredEight.com's projections for the Alberta election scheduled for May 5, 2015. These numbers were last updated on May 5 2015, and reflect the best estimates as of May 4, 2015, the last day of polls included in the model. You can click on all of the charts below to magnify them.

Click here to read an explanation of the new model, how it performed in 2012, and what to keep in mind when looking at these numbers.

Click here to read the detailed analyses from the main site concerning the Alberta election and new polls. 

Note that due to the Liberals not running a full slate of candidates, the projection adjusts the polls to reflect this fact by reducing the support of the Liberals according to their proportion of candidates. Support for other parties is also based on the number of candidates, rather than the average of the polls.

The vote and seat projections in the central columns reflect the best estimates based on the available polling data. The low and high projections are based on the over-estimation or under-estimation of support the polls are likely to make, while the minimum and maximum projections are designed to include 95% of potential outcomes.

The chart below shows how each party is classified in the model for the determination of the high and low ranges, and the probability that the result will fall within any of the projection ranges.

Based on these probabilities, there is a 58% chance that the outcome of the election for the Progressive Conservatives will fall between the best estimate (or average) projection and the high projection. There is an 70% chance that it will fall between the average and maximum projection, and so on. There is a 5% chance that the outcome will fall outside of the minimum and maximum ranges.

A detailed explanation of the vote and seat projection models and how the probabilities are calculated can be found here.

The projections are subject to the margin of error of the polls included in the model, as well as the inherent inability for the projection model to make perfect estimations of real-world dynamics. The projection ranges are a reflection of the degree of error polls have made in recent elections. The probabilities are based on how polls have differed from election results in the past.

The follow chart breaks the projection down by region.


The following chart lists the provincial polls currently included in the projection model that make up at least 95% of the weighted average, as well as the weight each poll carries. It also lists the media outlet that either commissioned or first reported the poll.

By including polls in the projection, no representation as to the accuracy or equivalency of the methods used is implied, nor should inclusion be seen as an acceptance, endorsement, or legitimization of their results. However, the weighting scheme takes reliability partly into account.

The following is a list of the current projections for all 87 of Alberta's ridings. These are the best estimates of likely outcomes if an election were held on the last day of polling. The high and low results are  the estimates of likely floors and ceilings, based on the high and low vote projection ranges. The probabilities listed beside each riding is the likelihood that, if an election were held on the last day of polling, the winning party identified by the model would actually win. It does not assign any probability to a particular trailing party winning the riding - if a projection gives the leading party a 75% chance of winning, there is a 25% chance that any of the other parties could win (though, in practice, most ridings are only contests between two parties).

These riding projections are not polls and are not necessarily an accurate reflection of current voting intentions in each riding.

The chart below shows the evolution of the seat and vote projections and ranges since the start of the campaign.