Question

Researcher B wants to quantify the variability in third graders’ weights, so he took a sample of 50 third graders across Connecticut elementary schools. However, he noticed that two third graders were usually heavy (it’s a glandular thing), and he does not want these unusual students to disproportionately influence this statistic of variability. What statistic of variability would you recommend that he use? To receive full credit, you must justify your answer.

Answer 1

Researcher B wants to quantify the variability in third graders' weights and takes a sample of 50 third graders. Now, he does not want unusual students to disproportionately influence this statistic of variability. So, he doesn't want outliers to affect his statistic of variability.

We know that, we do not need the extreme values, or the outliers to calculate interquartile range(IQR) , hence, researcher B should use IQR as a statistic of variability in this case.