Oprah Viewers Patiently Await Instructions*
Posted by Evan Herrnstadt on August 8, 2008
Craig Garthwaite and Tim Moore, economists at the University of Maryland, just posted a study that claims Oprah’s endorsement of Barack Obama netted him quite a few extra primary votes. From the abstract:
Candidates in major political contests are commonly endorsed by other politicians, interest groups and celebrities. Prior to the 2008 Democratic Presidential Primary, Barack Obama was endorsed by Oprah Winfrey, a celebrity with a proven track record of influencing her fans’ commercial decisions. In this paper, we use geographic differences in subscriptions to O! – The Oprah Magazine and the sale of books Winfrey recommended as part of Oprah’s Book Club to assess whether her endorsement affected the Primary outcomes. We find her endorsement had a positive effect on the votes Obama received, increased the overall voter participation rate, and increased the number of contributions received by Obama. No connection is found between the measures of Oprah’s influence and Obama’s success in previous elections, nor with underlying local political preferences. Our results suggest that Winfrey’s endorsement was responsible for approximately 1,000,000 additional votes for Obama.
Because data is only available at a county-wide level, the authors used a logit model for group-level observations, with the vote share as the limited dependent variable in one equation, and the participation rate as a share of the population in the other equation.
On top of the estimate that Obama got 1 million additional votes (I believe this refers to increased margin, as it comes from the vote share equation) thanks to Oprah, the authors also estimate (using the participation specification) that she increased total turnout by about 2 million.
Is this feasible? Well, according to Garthwaite and Moore, 8 million people watch Oprah’s show daily. Okay, but are these viewers all really so eager to follow their talisman? Let’s allow numbers to speak for themselves:
For example, in the case of Anna Karenina there were 11,648 units sold during the 12 weeks prior to inclusion in the [Oprah book] club. In the 12 weeks following inclusion, this book sold 643,122 units—a staggering increase of 5,421 percent.
* Shamelessly ripped off from The Onion.