Short articles

Short articles on statistical issues

Follow the featured links below or navigate from the side menu to find out more about common statistical issues. Each article presents a worked-out case study or a problem for you to solve.

Interpreting interactions - January 2015

Dear SCU,

Please help me with this intransigent referee!  I have two rye grass genotypes that show different responses to dry conditions. The growth pattern is delayed in Genotype B (p=0.001) but not in Genotype A (p-value n.s.). The referee keeps referring to “interactions”, but I think my data are clear enough. Can you help me respond to put an end to his endless whining? (read more...)

A puzzle for the intellectually curious - December 2014

Novel Drug A for treating hypertension was just released on the market after a well-publicized clinical trial showed it to be superior to Standard Drug B in lowering systolic blood pressure. Specifically, the study showed that a larger percentage of patients (65%) had a greater than 10 point drop in systolic blood pressure after just 1 month compared with patients on Drug B (50%). The results are summarized in the Table below: (read more...)