Projection and Methodology Update: Angus Reid's 9/16-18 ON Poll

The following poll has been added to the model:
Angus Reid's 9/16-18 ON poll (current weight among ON polls: 2%)
For a full list of included polls, see previous Projection posts.

Poor Angus Reid! After conducting a huge sample national poll (almost 4,000 respondents), "blackface" happened, and the horserace numbers became instantly outdated. It resorted to publishing the non-horserace results of this poll. Fortunately for us, Angus Reid did publish the voting intention numbers for ON, along with a detailed geographical breakdown, which I have used to update within-ON regional adjustments. Obviously, due to its age, this poll has a very low weight and does not affect ON provincial numbers much, but as you'll see below, many seat leads changed hands due to the changes in 905 adjustments (even though the overall effect on the expected value of the number of seats was quite neutral).

I have also made a methodological change for weighting standalone regional polls like this one. The old method - just use the regional weights designed for the differences between regional and national numbers - caused such polls to depreciate too slowly: their results are not only affected by the region's shifts relative to the country, but also by national shifts themselves. I have therefore made an adjustment to depreciate these polls more quickly (more details here), which marginally helped the Liberals as weight was removed from last week's Campaign Research ON poll: the Liberal lead there changed from 3.8% to 4.0%. This moved about 0.5 seat from the Tories to the Grits.

Projection as of the latest national poll (midpoint: September 23)
LIB - 150.7 (33.7%)
CON - 146.9 (36.4%)
BQ - 18.5 (5.1%)
NDP - 17.7 (12.5%)

GRN - 3.1 (9.1%)
IND - 0.5
PPC - 0.5
If you're new to my 2019 projections, view key interpretive information here.

Seat changing hands since the last projection:
- In ON, LIBs get Mississauga--Streetsville, Oakville, Mississauga--Lakeshore and Vaughan--Woodbridge back from CONs.