To get an approximate number of voters who are likely to vote on October 3, The duty applied the average turnout from 2012, 2014, and 2018 to the number of registered voters in 2022. For constituencies that were merged in those years, the data from the former constituency with the most weight in the new were used.
At the same time, we collected voting projections from Québec125, an independent electoral projection site. The statistical model aggregates the results of the polls of professional firms, weighted among other things according to the size of the sample, the date of publication and the demographic data of each constituency. It also takes into account an efficiency rating determined for each polling firm and voting history by constituency.
We then calculated the number of percentage points that separate the leader from the candidate who would come second according to these projections, then multiplied the number of voters who are likely to vote by this percentage.
For example, in Joliette, there are 57,124 registered voters this year and the average turnout for the last three elections is 73.37%, which gives us 41,914 voters who should vote this fall. The gap between the two favorite candidates is 6.6 percentage points: 41,914 x 0.066 = 2766 votes. If 1,384 people (half +1) who intended to vote for the favorite candidate give their vote instead to the second, it is the second who would win Joliette.