In a survey of introductory statistics students, an instructor asked her students how many flip-flops they have. Suppose that the intent is to study whether there is an association between number of flip-flops and a person€™s sex. 

a. Identify whether the study is an experiment or an observational study. Explain.
b. Identify the observational units.
c. Identify the explanatory and response variables. Also, for each variable identify whether it is categorical or quantitative.
d. Which of the following is the appropriate null hypothesis? Circle one.
A. There is an association between a person€™s sex and the number of flip-flops.
B. There is no association between a person€™s sex and the number of flip-flops.
C. On average, men have more flip-flops than women.
D. On average, men have fewer flip-flops than women.

e. Which of the following is the appropriate alternative hypothesis? Circle one.
A. There is an association between a person€™s sex and the number of flip-flops.

B. Th ere is no association between a person€™s sex and the number of flip-flops.
C. On average, men have more flip-flops than women.
D. On average, men have fewer flip-flops than women.
Here are a few summary statistics about the data:

f. In this context, which of the following is an (are) appropriate statistic value(s) to compare men to women? Circle all that apply.
A. 37 ˆ’ 13 = 24
B. 6.22 ˆ’ 2.54 = 3.68
C. 6 ˆ’ 1 = 5
D. 3.58 ˆ’ 2.96 = 0.62
Suppose that we want to use cards to carry out a randomization test of the appropriate hypotheses.
g. How many cards will we need? Circle one.
A. 37 

B. 13
C. 50 

D. Doesn€™t matter
The following is output from carrying out the randomization test using the Multiple Means applet.

h. On the histogram above, shade the region that depicts the p-value.

Transcribed Image Text:

Sample Sample size Sample mean Sample median SD 6.22 37 3.58 Women 6.00 2.54 Men 2.96 13 1.00 Mean = 0.010 SD = 1.214 30 60 90 120 150 180 -4 -2 2 Shuffled differences in means Count