ArchiveApril 7, 2015

How to interpret interaction terms

I keep referring to this issue in manuscript reviews, so I thought it worth a post. If you include an interaction term in a model, the statistical significance of the main effects and the interaction term tells you nothing about the interactive effect. This seems contrary to your intuition. Turns out the interactive effect may only significantly differ from zero for part of the covariate space...

Student fakes blackness to get into medical school

But the group bringing the lawsuit, Students for Fair Admissions, won a powerful PR ally this week: Vijay Chokal-Ingam, an Indian American who happens to be the brother of Fox comedy star Mindy Kaling, revealed that he won acceptance to medical school by claiming to be black. Frustrated at being rejected by medical schools in part because of mediocre test scores and a 3.1 grade point average...

Reviews matter: fascinating data from Tripadvisor

Those reviews carry demonstrable weight. A study by Cornell University’s Center for Hospitality Research found that for every percentage point a hotel improves its online reputation, its “RevPAR” (revenue per available room) goes up by 1.4 percent; for every point its reputation improves on a five-point scale, a hotel can raise prices by 11 percent without seeing bookings fall off. […] The...

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Professor and quant guy. Libertarian turned populist Republican. Trying to learn Japanese and play Spanish Baroque music on the ukulele.

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