David Lane's Academic Home Page

HyperStat Online

A Central Conclusion in Academically Adrift is Faulty

In a pessimistic view of the state of college education, Arum and Roksa claimed that 45% of students show no statistically significant gains in critical thinking. We demonstrate that their significance tests were conducted incorrectly and that it is likely that far fewer students show significant gains. However, this does not reflect on student learning as much as how hard it is to find a significant result with a sample size of one.

The Tukey hsd is not a post-hoc test

The Tukey hsd is often referrred to as a post-hoc test. It is more logical to call it an a priori test.


An free online introductory statistics book (includes videos)

YouTube Channel

Videos from OnlineStatBook

Rice Virtual Lab in Statistics

Simulations and demonstrations in statistics