STAT200 Quiz 10

A study done by the Center for Academic Integrity at Rutgers University surveyed 2116 students at 21 colleges and universities. Some of the schools had an "honor code" and others did not. Of the students at schools with an honor code, 7% reported having plagiarized a paper via the Internet, while at schools with no honor code, 13% did so. (Sacramento Bee, Feb 29, 2000, D1.) For this study, the relative risk of a student having plagiarized a paper via the Internet at a school with no honor code, compared to a school with an honor code is:

13/7 = 1.857

From our Minitab Class Survey or Excel Class Survey data then using Gender (Column 2) and if you would date someone of a different race (Column 25), what is the Pearson Chi-Square p-value for a test of a relationship between these two variables? The p-value is:

0.144; .144

The table above summarizes, by gender of respondent, the responses from 1,033 people to the question, "Do you smoke?" What are the odds of smoking (to not smoking) for a man?

0.47

From the Minitab Class Survey or Excel Class Survey data then using Gender (Column 2) and if you would date someone of a different race (Column 25), among males what is the risk of dating someone of a different race?

0.89

From our Minitab Class Survey or Excel Class Survey data then using Gender (Column 2) and if you would date someone of a different race (Column 25), what conclusion would you make regarding the relationship between the variables Gender and Date Different Race?

No statistical significant relationship exists in the population because the p-values is greater than 0.05

The table above summarizes, by gender of respondent, the responses from 1,033 people to the question, "Do you smoke?" What is the odds ratio for men smoking (to not smoking) compared to women?

1.15

A survey asked people how often they exceed speed limits. The data are then categorized into the above contingency table of counts showing the relationship between age group and response. What is the relative risk of always exceeding the speed limit for people under 30 compared to people over 30?

2.5

The table above shows the counts by gender and highest degree attained for 498 respondents in the General Social Survey. What percent of the sample did not graduate from high school?

20.3%

The relative risk of allergies for children of parents who smoke compared to children of parents who don't smoke is 3.0. Suppose that the risk of allergies for the children of non-smokers is 0.15 (15%). What is the risk of allergies for the children of smokers?

45%

The table above shows the responses from a sample of 680 people in the General Social Survey to the question, "Do you sometimes drink more than you think you should?" What is the risk (or percentage) of men thinking they drank more than they should?

46.0%

The table above shows the opinions of 953 respondents in the General Social Survey to the question "If your party nominated a woman for President, would you vote for her if she were qualified for the job?" What percent of respondents who said "yes" to voting for a woman president were female?

59.3%

The table above shows the counts by gender and highest degree attained for 498 respondents in the General Social Survey. What percent of the sample were males with no high school degree?

9.8%

Which of the following variables COULD be used in a Chi-Square analysis?

All of the above

The table above shows the opinions of 953 respondents in the General Social Survey to the question "Everything considered, would you say that in general, you approve or disapprove of wiretapping?" The purpose of examining the data is to see if there is a gender difference in how people would respond to this question. To test whether there is a relationship in the population between gender and support for wiretapping, the chi-square statistic = 11.7 and the p-value = 0.001. Are the results statistically significant or not statistically significant and what is the conclusion?

The results are statistically significant. The conclusion is that there is a relationship between gender and approving of the practice of wiretapping.

Students in a statistics class were asked, "With whom do you find it easier to make friends:person of the same sex, person of opposite sex, or no preference?" A table summarizing the responses by gender is given below. Results for a chi-square test for these data were: Chi-Sq = 7.15 DF=2 P-value = 0.028. Assume these students represent a random sample of all students. Based on the chi-square test, what conclusion can be made about the relationship between gender and response to the question about friends, using a = 0.05? In the population:

The relationship is statistically significant so there is a relationship.

Which of the following is the BEST statement of the alternative hypothesis for conducting a Chi-Square analysis?

The variables ARE statistically related in the population

The table above shows the opinions of 1447 respondents in the General Social Survey to the question "Do you favor or oppose the death penalty for persons convicted of murder?" The purpose of examining the data is to see if there is a gender difference in how people would respond to this question. State the alternative hypotheses for this study.

There is a relationship in the population between gender and opinion on the death penalty.

The table above shows the opinions of 321 respondents from the General Social Survey by whether they owned a gun (or not) and whether they favored (or opposed) a law requiring a permit to own a gun. What is the correct alternative hypothesis for this survey?

There is a relationship in the population between gun ownership and opinion regarding gun law permit

The table above shows the opinions of 1027 respondents in the General Social Survey to the question "Is there any area right around here - that is, within a mile - where you would be afraid to walk alone at night?" The purpose of examining the data is to see if there is a gender difference in how people would respond to this question. State the null hypotheses for this study.

There is no relationship in the population between gender and response to the question

A statistically significant relationship between two categorical variables is illustrated in the sample as one that

is large enough that it is unlikely to have occurred in the observed sample if there is no relationship in the population