Name AP Statistics Chapter 4 Review 1. In a study of the link between high blood pressure and cardiovascular disease, a group of white males aged 35 to 64 was followed for 5 years. At the beginning of the study, each man had his blood pressure measured and it was classified as either "low" systolic blood pressure (less than 140 mm Hg) or "high" blood pressure (140 mm Hg or higher). The following table gives the number of men in each blood pressure category and the number of deaths from cardiovascular disease during the 5-year period. Blood pressure Deaths Total Low 10 2000 High 5 3500 Based on these data, which of the following statements is correct? A. These data are consistent with the idea that there is a link between high blood pressure and death from cardiovascular disease. B. The mortality rate (proportion of deaths) for men with high blood pressure is 5 times that of men with low blood pressure. C. These data probably understate the link between high blood pressure and death from cardiovascular disease, because men will tend to understate their true blood pressure. D. Although there were more deaths in the high blood pressure group, this is expected, because there were 1500 more men in that group. E. All of the above. Use the following information for questions 2 through 6. A review of voter registration records in a small town yielded the following table of the number of males and females registered as Democrat, Republican, or some other affiliation. Male Female Democrat 300 600 Republican 500 300 Other 200 100 2. The proportion of males that are registered as Democrats is A. 300 B. 30 C. 0.33 D. 0.30 E. 0.15 3. Your percentage from question number 12 is part of A. The marginal distribution of political party registration. B. The marginal distribution of gender. C. The conditional distribution of gender among Democrats. D. The conditional distribution of political party registration among males. E. The conditional distribution of males within gender.
4. The proportion of registered Democrats that are male is A. 300 B. 33 C. 0.33 D. 0.30 E. 0.15 5. Your percentage from question number 14 is part of A. The marginal distribution of political party registration. B. The marginal distribution of gender. C. The conditional distribution of gender among Democrats. D. The conditional distribution of political party registration among males. E. The conditional distribution of males within gender. 6. Which of the following graphs accurately represents the distribution for political party registration for each gender? A. D. B. E. C.
Use the following information for questions 7 10. Below is a two-way table summarizing the number of cylinders in selected car models manufactured in six different countries in the 1990 s. Number of cylinders 4 5 6 8 Total France 0 0 1 0 1 Germany 4 1 0 0 5 Italy 1 0 0 0 1 Japan 6 0 1 0 7 Sweden 1 0 1 0 2 U.S.A. 7 0 7 8 22 Total 19 1 10 8 38 7. The percentage of all cars listed in the table with 4-cylinder engines is A. 19%. B. 21%. C. 50%. D. 80%. E. 91%. 8. The percent of cars with 4-cylinder engines that are made in Germany is A. 10.5%. B. 21%. C. 50%. D. 80%. E. 91%. 9. Which of the following is a marginal distribution? A. The percentage of all four-cylinder cars manufactured in Germany. B. The number of four-cylinder cars manufactured in Germany. C. The percentage of all cars manufactured in each country. D. The percentage of cars manufactured in Germany for each number of cylinders. E. The numbers 4, 5, 6, 8. 10. From this table, we might conclude that A. there is a strong association between country of origin and number of cylinders. B. about 18% of the cars sold in the United States were manufactured in Japan. C. these data could be more effectively presented with a box plot. D. the only eight cylinder cars in this data set were manufactured in Germany. E. All the cars on Italian roads have four cylinders. 11. A random sample of 100 students in grades 10 through 12 were sampled and asked their year in school and whether they were involved in interscholastic sports, intramural sports, or no sports. The results are summarized in the segmented bar graph on the next page.
Based on this graph, which of the following statements is true? A. More seniors are involved in interscholastic sports than sophomores. B. There is no association between year in school and whether students are involved in sports. C. There were more seniors in the sample than juniors. D. Juniors have the highest percentage participation in intramurals. E. Less than half the seniors are involved in either interscholastic or intramural sports. 12. Suppose we measure a response variable Y for several values of an explanatory variable X. A scatterplot of log Y versus log X looks approximately like a negatively-sloping straight line. We may conclude that A. the rate of growth of Y is positive, but slowing down over time. B. an exponential growth model would approximately describe the relationship between Y and X. C. a power model would approximately describe the relationship between Y and X. D. the relationship between Y and X is a positively-sloping straight line. E. the residual plot of the regression of log Y on log X would have a U-shaped pattern suggesting a non-linear relationship. 13. Using least-squares regression on data from 1990 through 2009, I determine that the (base 10) logarithm of the population of a country is approximately described by the equation. Which of the following is the predicted population of the country in the year 2010? A. 6.6 B. 735 C. 2,000,000 D. 3,981,072 E. 33,000,000 14. Which of the following would provide evidence that a power law model describes the relationship between a response variable y and an explanatory variable x? A. A normal probability plot of the residuals of the regression of log y versus log x looks approximately linear. B. A normal probability plot of the residuals of the regression of log y versus x looks approximately linear. C. A scatterplot of log y versus x looks approximately linear. D. A scatterplot of y versus log x looks approximately linear. E. A scatterplot of log y versus log x looks approximately linear.
15. Suppose the relationship between a response variable y and an explanatory variable x is modeled well by the equation A. A plot of y against x. B. A plot of y against log x. C. A plot of log y against x. D. A plot of 10 y against x. E. A plot of log y against log x.. Which of the following plots is most likely to be roughly linear? Use the following information for questions 16 and 17. Like most animals, small marine crustaceans are not able to digest all the food they eat. Moreover, the percentage of food eaten that is assimilated (that is, digested) decreases as the amount of food eaten increases. A scatterplot of this relationship for a certain species of crustacean (at right) indicates that it is non-linear. However, a scatterplot of ln Assimilation versus ln Food Intake is strongly linear. Below is a computer regression analysis of the transformed data (note that natural logarithms are used). Predictor Coef SE Coef T P Constant 6.3324 0.5218 12.14 0.000 ln Food Intake -0.6513 0.1047-6.22 0.000 S = 0.247460 R-Sq = 84.7% R-Sq(adj) = 82.5% 16. Which of the following best describe the model that is given by this computer printout? A. A power model with equation B. An exponential model with equation C. A power model with equation D. An exponential model with equation E. A power model with equation
17. If, as described above, the scatterplot of ln Assimilation versus ln Food Intake is strongly linear, which of the following best describes the residual plot for the regression of these two variables? A. A roughly straight line. B. A U-shaped pattern, with positive residuals for low and high values of food intake and negative residuals in between. C. A U-shaped pattern, with negative residuals for low and high values of food intake and positive residuals in between. D. A curved pattern similar to the scatterplot of the variables Food Intake and Assimilation before the logarithmic transformation. E. A random scattering of points on either side of the line whose equation is residuals = 0. Use of the Internet worldwide increased steadily from 1990 to 2002. A scatterplot of this growth (at right) shows a strongly non-linear pattern. However, a scatterplot of ln Internet Users versus Year is much closer to linear. Below is a computer regression analysis of the transformed data (note that natural logarithms are used). Predictor Coef SE Coef T P Constant -951.10 43.45-21.89 0.000 Year 0.4785 0.02176 21.99 0.000 S = 0.2516 R-Sq = 98.2% R-Sq(adj) = 98.0% 18. Use Scenario 12-8. Which of the following best describe the model that is given by this computer printout? A. A power model with equation B. A power model with equation C. A power model with equation D. An exponential model with equation E. An exponential model with equation
Chapter 4 Review Answer Section MULTIPLE CHOICE 1. ANS: A PTS: 1 TOP: Compare two categorical variables (not in two-way table. 2. ANS: D PTS: 1 TOP: Conditional distribution--calculation 3. ANS: D PTS: 1 TOP: Conditional distribution--identification 4. ANS: C PTS: 1 TOP: Conditional distribution--calculation 5. ANS: C PTS: 1 TOP: Conditional distribution--identification 6. ANS: E PTS: 1 TOP: Segmented bar graphs 7. ANS: C PTS: 1 TOP: Marginal distribution-calculation 8. ANS: B PTS: 1 TOP: Conditional distribution--calculation 9. ANS: C PTS: 1 TOP: Marginal distribution-identification 10. ANS: A PTS: 1 TOP: Interpret two-way table 11. ANS: D PTS: 1 TOP: Interpret segmented bar graph 12. ANS: C PTS: 1 TOP: Interpreting log-log scatterplot 13. ANS: D PTS: 1 TOP: Prediction from log Y vs. X regression 14. ANS: E PTS: 1 TOP: Power functions and transformations 15. ANS: C PTS: 1 TOP: Exponential functions and transformations 16. ANS: A PTS: 1 TOP: Model/Equation for log-log transformation 17. ANS: E PTS: 1 TOP: Residuals for good linear fit 18. ANS: D PTS: 1 TOP: Model/Equation for semi-log transformation