# Question: Statisticians often need to know the shape of a population

Statisticians often need to know the shape of a population to make inferences. Suppose that you are asked to specify the shape of the population of weights of all college students.

a. Sketch a graph of what you think the weights of all college students would look like.

b. The following data give the weights (in pounds) of a random sample of 44 college students (F and M indicate female and male, respectively).

i. Construct a stem-and-leaf display for these data.

ii. Can you explain why these data appear the way they do?

c. Construct a back-to-back stem-and-leaf display for the data on weights, placing the weights of the female students to the left of the stems and those of the male students to the right of the stems. (See Exercise 2.89 for an example of a back-to-back stem-and-leaf plot.) Does one gender tend to have higher weights than the other? Explain how you know this from the display.

a. Sketch a graph of what you think the weights of all college students would look like.

b. The following data give the weights (in pounds) of a random sample of 44 college students (F and M indicate female and male, respectively).

i. Construct a stem-and-leaf display for these data.

ii. Can you explain why these data appear the way they do?

c. Construct a back-to-back stem-and-leaf display for the data on weights, placing the weights of the female students to the left of the stems and those of the male students to the right of the stems. (See Exercise 2.89 for an example of a back-to-back stem-and-leaf plot.) Does one gender tend to have higher weights than the other? Explain how you know this from the display.

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