Exercise

t-test vs. Mann-Whitney U test

A t-test and a Mann-Whitney U test can both assess whether two groups are significantly different. An independent t-test is a parametric test assessing the means of the groups while the Mann-Whitney U test is non-parametric and assesses the rank order of the groups. If the data is normally distributed, either test can be performed but the Mann-Whitney U test is less sensitive and makes fewer assumptions about the underlying data.

In this exercise, you'll run both tests on the same dataset to assess whether your A/B groups of students that had access to a laptop/desktop or a smartphone for course work spent more time on social media during Covid-19.

The covid dataset, and the pwr and effectsize packages have been loaded for you.

Instructions 1/4

25 XP
    1
    2
    3
    4
  • Run a two-tailed independent sample t-test on Time.spent.on.social.media by Medium.for.online.class of the covid dataset treating the variances as equal, then find the effect size, Cohen's d.