Reconsider Exercise 6.2.1 in which an instructor collected data on prices (in dollars) paid by students for their most recent haircut, also recording each student’s sex.
A 95% confidence interval for μ_female − μ_male turned out to be (12.17, 52.23). For each of the following, indicate whether it provides a correct or incorrect interpretation/conclusion from this interval.
a. Between 12.17% and 52.23% of females in the population paid more than males for their haircut.
b. About 95% of all females in the population paid between $12.17 and $52.23 more than males for their haircut.
c. About 95% of all females in the sample paid between $12.17 and $52.23 more than males for their haircut.
d. We can be 95% confident that the probability is between 12.17% and 52.23% that females in the population pay more than males for their haircut.
e. We can be 95% confident that the average price paid for a haircut in this population is between $12.17 and $52.23.
f. We can be 95% confident that the average price paid for a haircut by a female in this population is higher than the average price paid by males in this population by between $12.17 and $52.23.
g. We can be 95% confident that all females in the population paid more than all males for their haircut by between $12.17 and $52.23.
h. We can be 95% confident that most females in the population paid more than most males for their haircut by between $12.17 and $52.23.
i. We can be 95% confident that females in the population paid more on average than males for their haircut by between $12.17 and $52.23.

Data from previous exercise

Suppose that randomly sampled college students are asked how many hours they typically spend online each day. You conduct a two-sided test of the null hypothesis that μ_females − μ_males = 0, and you also calculate a 95% confidence interval for μ_females − μ_males.