Wednesday, 5 June 2013

Warning: Polls May Be Hazardous to Your Health

Pollsters have been insisting that even though fewer people can be reached by telephone today, polling still is a valid way of predicting electoral outcomes.

They've turned to elelctronic polling and elaborate models that are supposed to message data so that the population reached by polling reflects the electorate as a whole.

But recently there have been some thundering examples.  The first was the way that Romney forces underestimated Obama strength in the 20012 US Presidential elction. On Tuesday Gallup officials said  they had analyzed their performance and come up with four factors that led to the skewing of their prediction toward the Republicans.

The New York Times reported that "Gallup’s model for identifying those most likely to vote — a series of seven questions — seemed to have failed in 2012, and the organization is re-evaluating its formula for ranking voters who will turn out.

"Just as technology has changed the way campaigns work, it has altered the way survey researchers gather data. A change in the way that Gallup called respondents on land lines may have been a contributing factor that led to its sample to be older and more Republican. Half of their respondents, however, were reached on cellphones — a proportion that is at or above industry standards.

"In addition, there were too many respondents from certain time zones. In the South and the Midwest, there were more respondents from the Central Time Zone, which tends to be more Republican, than the Eastern Time Zone, which skews Democratic.

"Finally, the way Gallup asked callers about their race overrepresented some groups."

Corrcting these problems should not be insurmountable obstacles, but nevertheless it would be wise for Canadian pollsters and political top dogs to consider what Gallup found.  Both BC and Alberta have had recent elections full of suprises, too. 

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