Question

Guessing Ages On the first day of a statistics class, 37 students took a survey in which they were asked to guess the age of their instructor. These guesses are given below:

47 43 50 38 37 38 37 42 42 41
40 37 35 33 34 45 45 43 38 39
37 32 40 30 32 45 46 35 40 40
33 42 42 40 46 40 35

a) How many cases are in this data set?

b) How many variables are in this data set? (Classify the type of each variable.)

c) Create an appropriate graphical display for this data.

d) Describe the distribution of guesses.

e) Compute the mean, median, standard deviation, IQR and range for the guesses.

f) Which summary statistics would be most appropriate to summarize the center and variability of the data?

g) If the instructor had shown the class a photo of his 12-year-old son and asked the students to guess his son's age, would you expect the standard deviation of guesses about his son's age be smaller or larger than the standard deviation of guesses about the instructor's age? Explain.

h) One other student, not listed above, misread the instructions and answered with his or her own age (20) rather than guessing the instructor's age. If this student's response were included in the data set, what would happen to the mean? The median? The standard deviation? The IQR?

i) Was this an observational study or an experiment?

Answer 1