# Question

The data in the accompanying table is from the paper “Gender Differences in Food Selections of Students at a Historically Black College and University” (College Student Journal [2009]: 800–806). Suppose that the data resulted from classifying each person in a random sample of 48 male students and each person in a random sample of 91 female students at a particular college according to their response to a question about whether they usually eat three meals a day or rarely eat three meals a day.

a. Is there evidence that the proportions falling into each of the two response categories are not the same for males and females? Use the X2 statistic to test the relevant hypotheses with a significance level of .05.

b. Are your calculations and conclusions from Part (a) consistent with the accompanying Minitab output? Expected counts are printed below observed counts Chi-Square contributions are printed below expected countsa. Is there evidence that the proportions falling into each of the two response categories are not the same for males and females? Use the X2 statistic to test the relevant hypotheses with a significance level of .05.

b. Are your calculations and conclusions from Part (a) consistent with the accompanying Minitab output? Expected counts are printed below observed counts Chi-Square contributions are printed below expected counts

c. Because the response variable in this exercise has only two categories (usually and rarely), we could have also answered the question posed in Part (a) by carrying out a two-sample z test of H0: p1 2 p2 5 0 versus Ha: p1 2 p2 2 0, where p1 is the proportion who usually eat three meals a day for males and p2 is the proportion who usually eat three meals a day for females. Minitab output from the two-sample z test is shown on the next page. Using a significance level of .05, does the two-sample z test lead to the same conclusion as in Part (a)?

Difference 5 p (1) - p (2) Test for difference 5 0 (vs not 5 0): Z 5 1.53 P-Value 5 0.127

d. How do the P-values from the tests in Parts (a) and (c) compare? Does this surprise you? Explain?

a. Is there evidence that the proportions falling into each of the two response categories are not the same for males and females? Use the X2 statistic to test the relevant hypotheses with a significance level of .05.

b. Are your calculations and conclusions from Part (a) consistent with the accompanying Minitab output? Expected counts are printed below observed counts Chi-Square contributions are printed below expected countsa. Is there evidence that the proportions falling into each of the two response categories are not the same for males and females? Use the X2 statistic to test the relevant hypotheses with a significance level of .05.

b. Are your calculations and conclusions from Part (a) consistent with the accompanying Minitab output? Expected counts are printed below observed counts Chi-Square contributions are printed below expected counts

c. Because the response variable in this exercise has only two categories (usually and rarely), we could have also answered the question posed in Part (a) by carrying out a two-sample z test of H0: p1 2 p2 5 0 versus Ha: p1 2 p2 2 0, where p1 is the proportion who usually eat three meals a day for males and p2 is the proportion who usually eat three meals a day for females. Minitab output from the two-sample z test is shown on the next page. Using a significance level of .05, does the two-sample z test lead to the same conclusion as in Part (a)?

Difference 5 p (1) - p (2) Test for difference 5 0 (vs not 5 0): Z 5 1.53 P-Value 5 0.127

d. How do the P-values from the tests in Parts (a) and (c) compare? Does this surprise you? Explain?

## Answer to relevant Questions

In a study of high-achieving high school graduates, the authors of the report “High-Achieving Seniors and the College Decision” (Lipman Hearne, October 2009) surveyed 828 high school graduates who were considered ...The paper “Overweight Among Low-Income Preschool Children Associated with the Consumption of Sweet Drinks” (Pediatrics [2005]: 223–229) described a study of children who were underweight or normal weight at age 2. ...The press release titled “Nap Time” (pewresearch.org, July 2009) described results from a nationally representative survey of 1488 adult Americans. The survey asked several demographic questions (such as gender, age, and ...The article “Cooperative Hunting in Lions: The Role of the Individual” (Behavioral Ecology and Sociobiology [1992]: 445–454) discusses the different roles taken by lionesses as they attack and capture prey. The authors ...The report “Fatality Facts 2004: Bicycles” (Insurance Institute, 2004) included the following table classifying 715 fatal bicycle accidents according to time of day the accident occurred. a. Assume it is reasonable to ...Post your question

0