Pundits' Guide: Data Analysis in Other Canadian Political Blogs: Paulitics vs Ipsos-Reid

Friday, June 26, 2009

Data Analysis in Other Canadian Political Blogs: Paulitics vs Ipsos-Reid

In a very good demonstration of why I stay away from polling data altogether, readers might be interested in a series of blogposts that started as a methodological debate between the author of the Paulitics Polls blog and the vice-president of Ipsos-Reid, and have intensified from there.

Essentially, Paul was asking statistically and methodologically why, in his examination of Ipsos-Reid polls versus their competitors', a consistent gap appeared between their results for two of the political parties. Ipsos-Reid VP John Wright challenged the assertion, but did not respond to Paul's methodological points in as thorough-going a fashion as Paul had hoped for. Paul introduced more data to prove his points, while Wright amended his originally claimed source for his data, but otherwise demurred from further detailed discussion. U.S. pollster John Zogby also appears to have entered the debate in the comments section.

There are a number of good aggregations of public domain polling data for federal politics, including:

The list of polls maintained at the Wikipedia page
NoDice.ca federal polls page - maintained by David, a graduate student at St. Francis Xavier
Paulitics Polls - maintained and written by Paul, an M.A. in political science from Carleton University
PollingReport.ca - (which I've just discovered you can now follow on Twitter) maintained by ~~Kerry, another M.A. grad~~ Kelly, an M.Sc. grad with a B.A. in Math [thanks to the commenter for correcting me]
ThreeHundredEight.com - maintained by Éric, whose academic credentials I don't know, but he publishes his methodological approach here
John Wright earlier claimed there was a complete set of polling results at Elections Canada. Although I can't claim to know every nook and cranny of that website, I do know it better than many folks, and I've honestly never come across any such data there.

The points of debate between Paul and Wright seem to boil down to:

in making claims about differences between Ipsos-Reid polls and other firms' polls, what is the source of the other polls, and which source has the most complete set of other polls
in making claims about differences between Ipsos-Reid polls and other firms' polls, is it valid to use an unweighted average of averages
why has Ipsos-Reid not followed the example set by other polling firms in publicly releasing polling data details
why would Paul invest so much effort to investigate this question

The two have a history of sparring over the same topic, but the current set of blogposts does make for an interesting and real-life question about the validity of different ways to assess polling methodologies. I know I learned a lot from reading it all.

Here are the blogposts in what I think is chronological order:

Labels: Data Analysis, Opinion Research, Polling Data

6 Comments:

MrvnMouse said...: Pollingreport.ca is maintained by Kelly, a MSci grad. with a BMath.; June 27, 2009 8:36 AM
The Pundits' Guide said...: Dang, I knew it was either Kelly or Kerry, but didn't have access to my email archives to double-check, and it's nowhere listed on his site. Will correct immediately, and thank you for taking the trouble to point out my error.; June 27, 2009 9:55 AM
Jose Sean said...: Politicians are always like that...; July 6, 2009 4:49 AM
Éric said...: I have a BA in History.; July 30, 2009 9:34 AM
The Pundits' Guide said...: Thanks Éric. Just catching up on your reading, I see!; July 30, 2009 9:46 AM
Éric said...: Like the narcissist I am, I Google my own site periodically.

By the way, Beau's? Are you by any chance from Vankleek Hill or nearby?; July 30, 2009 12:51 PM