In a survey of introductory statistics students, an instructor asked her students how many flip- flops they have. Suppose the intent is to study whether there is an association between the number of flips – flops and gender. 1. Identify the explanatory and response variables. Also, for each variable identify whether it is categorical or quantitative.
2. Which of the following is the appropriate null hypothesis?

a. On average, men have more flip-flops than women.
b. There is no association between a person’s sex and the number of flip-flops that they own.
c. There is an association between a person’s sex and the number of flip-flops that they own.
d. On average, men have fewer flip-flops than women.

3. Which of the following is the appropriate alternative hypothesis?

a. There is an association between a person’s sex and the number of flip-flops that they own.
b. On average, men have more flip-flops than women.
c. On average, men have fewer flip-flops than women.
d. There is no association between a person’s sex and the number of flip-flops that they own.

Here are a few summary statistics about the data:

Sample size Sample mean Sample median Sample SD
Women 37 6.22 6 3.58
Men 13 2.54 1 2.96