a. Why researchers are interested in describing measures of the center and measures of variation of a data set?
b. What is an "arithmetic mean" ? Does it have the same meaning as the word "average"?
c. The average of data set is influenced by extreme values while the median is not. In other words, the median is not resistant to outliers but the average is not.
d. The range is the most obvious measure of variability or spread out of values in a data set but it is not the best measure compared to standard deviation.
e. Interpret the meaning of "standard deviation" if the standard deviation of a set of numbers is 2 and the arithmetic mean is 3.