Students often believe that statistical significance is the only determinant of whether a quantitative result is "important." In this paper, I review traditional null hypothesis statistical testing to identify what questions inferential statistics can and cannot answer, including statistical significance, effect size and direction,…

Personalized, online homework was used to supplement textbook homework, quizzes, and exams for one section of a course in material and energy balances. The objective of this study was to test the hypothesis that students using personalized, online homework earned better grades in the course. The online homework system asks the same questions of…

Unless the sample encompasses a substantial portion of the population, the standard error of an estimator depends on the size of the sample, but not the size of the population. This is a crucial statistical insight that students find very counterintuitive. After trying several ways of convincing students of the validity of this principle, I have…