Reference no: EM13913423

Question-

1. If the result of a hypothesis test for a proportion is statistically significant, then

A) the population proportion must equal the null value.

B) the null hypothesis is rejected.

C) the alternative hypothesis is rejected.

2. Suppose a 95% confidence interval for p, the proportion of drivers who admit that they sometimes run red lights when no one is around, is 0.29 to 0.38. Which of the following statements is false?

A) It is plausible that a majority of all drivers would admit that they sometimes run red lights when no one is around.

B) A test of Ho: r = 0.3 versus Ha: r≠ 0.3 would not be rejected using a = 0.05.

C) A test of Ho: r = 0.5 versus Ha: r≠ 0.5 would be rejected using a = 0.05.

D) It is plausible that about 37% of all drivers would admit that they sometimes run red lights when no one is around.

3. Which of the following is not a correct way to state a null hypothesis?

A) Ho:

B) Ho: µ = 0.5

C) Ho: µ = 0

D) Ho: µd = 10

4. It is known that for right-handed people, the dominant (right) hand tends to be stronger. For left-handed people who live in a world designed for right-handed people, the same may not be true. To test this, muscle strength was measured on the right and left hands of a random sample of 15 left-handed men and the difference (left - right) was found. The alternative hypothesis is one-sided (left hand stronger). The resulting t-statistic was 1.90. Assuming the conditions are met, based on the t-statistic of 1.90 the appropriate conclusion for this test using ? = 0.05 and using T-Table is

A) The results are statistically significant so the left hand appears to be stronger.

B) The results are statistically significant so the left hand does not appear to be stronger.

C) The results are not statistically significant so there is not enough evidence to conclude the left hand appears to be stronger.

5. The maximum distance at which a highway sign can be read is determined for a sample of young people and a sample of older people. The mean distance is computed for each age group. What is the most appropriate null hypothesis about the means of the two groups?

A) The population means are different.

B) The sample means are the same.

C) The sample means are different.

D) The population means are the same.

6. A shopper wanted to test whether there was a difference in the average waiting times at the check-out counter among 5 different supermarkets. She selected a random sample of 20 shoppers from each of the five supermarkets. What is the alternative hypothesis for this situation?

A) The average waiting time for each of the 100 shoppers is different.

B) The average waiting time to check out is 25 minutes for all five supermarkets.

C) The average waiting time to check out is not the same for all five supermarkets.

D) The average waiting time to check out is the same for all five supermarkets.

7. On a survey conducted at a university, students were asked how they felt about their weight (about right, overweight, or underweight), and also were asked to record their grade point average (GPA). There were 235 responses, with 160 saying their weight was about right, 50 said they were overweight, and 17 underweight. The question of interest is whether mean GPA is the same or differs for different weight attitude populations. Minitab output for the study is given above. What is the appropriate conclusion to draw from this analysis?

A) Overweight students should go on a diet to lose weight because this will result in a higher GPA.

B) There is a significant difference among the mean GPAs of students in the three weight attitude groups.

C) If a student is underweight he (she) should gain weight in order to raise his (her) GPA.

D) There is no significant difference among the mean GPAs of students in the three weight attitude groups.

8. When conducting a chi-square test on two variables, a statistically significant relationship is illustrated when:

A) the sample produces a small relationship that is unlikely to have occurred even if there is no difference in the population.

B) the sample produces a large relationship that is likely to have occurred even if there is no difference in the population.

C) the sample produces a large relationship that is unlikely to have occurred even if there is no difference in the population.

D) the sample produces a small relationship that is likely to have occurred even if there is no difference in the population.

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

A) The variables are NOT statistically related in the population

B) The variables ARE statistically related in the population

C) The variables are NOT statistically related in the sample

D) The variables ARE statistically related in the sample

10. 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?

A) 51.2%

B) 11.9%

C) 88.1%

D) 59.3%

11. The table above shows the opinions of 908 respondents in the General Social Survey to the question "Do you believe there is life after death?" What percent of respondents who believe in life after death were male?

A) 40.9%

B) 72.1%

C) 31.1%

D) 27.9%

12. A study on the use of seat belts versus belted booster seats for children ages 4 and 5 reported that "Using seat belts instead of booster seats was associated with increased risk for serious injury in an accident; the relative risk was 2.4." Based on this, it can be concluded that for this study:

A) The percent of children ages 4 and 5 in a booster seat was 2.4 times higher than the percent of children wearing seatbelts.

B) Children ages 4 and 5 in a booster seat were 2.4 times more likely to have serious injuries in an accident than were children wearing seatbelts

C) Children ages 4 and 5 wearing seatbelts were 2.4 times more likely to have serious injuries in an accident than were children in a booster seat.

D) The percent of children ages 4 and 5 wearing seatbelts was 2.4 times higher than the percent of children in a booster seat.

13. 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?

A) 5%

B) 30%

C) 3%

D) 45%

14. Pick the choice that best completes the following sentence. If a relationship between two variables is called statistically significant, it means the investigators think the variables are

A) not related in the population represented by the sample.

B) related in the population represented by the sample.

C) related in the sample due to chance alone.

D) very important.

15. 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. State the null hypotheses for this study.

A) There is a relationship in the sample between gender and approval of wiretapping

B) There is no relationship in the sample between gender and approval of wiretapping

C) There is no relationship in the population between gender and approval of wiretapping

D) There is a relationship in the population between gender and approval of wiretapping

16. 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.

A) There is a relationship in the sample between gender and opinion on the death penalty.

B) There is no relationship in the sample between gender and opinion on the death penalty.

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

D) There is no relationship in the population between gender and opinion on the death penalty.

17. If the correlation between a response variable Y and explanatory variable X is - 0.3, what is the value that defines how much variation in Y is explained by X?

A) - 9%

B) 9%

C) - 3%

D) 3%

18. Describe the type of association shown in the scatterplot above:

A) Positive linear association

B) Negative curvilinear association

C) Negative linear association

D) Positive curvilinear association

19. Which one of the following is not appropriate for studying the relationship between two quantitative variables?

A) Scatterplot

B) Bar chart

C) Regression

D) Correlation

20. In the simple linear regression equation y = b0 + b1x, the term b1 represents the

A) estimated slope.

B) estimated intercept.

C) estimated or predicted response.

D) explanatory variable.

21. Which of the following can not be answered from a regression equation?

A) Estimate whether the linear association is positive or negative.

B) Predict the value of y at a particular value of x.

C) Estimate whether the association is linear or non-linear

D) Estimate the slope between y and x.

22. A scatterplot above shows the price of a book (y variable) versus the number of pages in the book (x variable) is shown for 15 books in a professors office. In addition, the symbol "o" shows that the book was a hardcover book, while the symbol "+" shows that the book was a softcover book. What is the main difficulty with using a regression line to analyze these data?

A) Response variable is not quantitative

B) Presence of one or more outliers

C) Curvilinear data

D) Inappropriately combining groups

23. The value of a correlation is reported by a researcher to be r = - 0.5. Which of the following statements is correct?

A) The x-variable explains 50% of the variability in the y-variable.

B) The x-variable explains 25% of the variability in the y-variable.

C) The x-variable explains -25% of the variability in the y-variable.

D) The x-variable explains -50% of the variability in the y-variable.

24. From the regression output, what is the value of the correlation between Height and Weight?

A) - 0.612

B) 0.612 or - 0.612

C) 0.375

D) 0.612

25. Which variable in the Regression Equation represents the independent variable (also known as the predictor or explanatory variable)?

A) Weight

B) Height