Health Sciences homework help. This document of QRB 501 Week 5 Discussion Questions and Summary Version 2 consists of: DQ 1: Does all statistical data have a mean, median, or mode? Why? When is the mean the best measure of central tendency? When is the median the best measure of central tendency? DQ 2: What is the middle? If we have student scores of 4.0, 3.7, 3.7, 3.7, and 1.0, the average would be 3.2, whereas both the median and the mode would be 3.7. Is one of them truly in the middle? How dispersed is this list? That is, how much do the scores vary from the middle? Consider a routine task you do daily. Which matters most, the average time it takes to complete the task or the most frequent amount of time? How much does the time spent on the task vary? How would you go about finding the middle of the process? Summary