1. For the scatterplot below, choose the correct correlation value. A) 0.92 B) 0.98 C) 0.26 D) 0 E) 1 2. For the scatterplot below, choose the correct correlation value. A) 0.92 B) 0.98 C) 0.26 D) 1 E) 1 3. For the scatterplot below, choose the correct correlation value. A) 0.92 B) 0.98 C) 0.26 D) 1 E) 1 Use the information below for the questions that follow: A regression analysis between the time spent writing a paper (y, in hours) and length of paper (x, in pages) yielded the following regression equation and plot: Time = 1.3 + 1.2 Length 4. Which of the following is a correct interpretation of the slope? A) For every 1 page increase in the length of the paper, the time spent writing the paper will increase, on average, by 1.2 hours. B) For every 1 page increase in the length of the paper, the time spent writing the paper will increase, on average, by 1.3 hours. C) For every 1.2 page increase in the length of the paper, the time spent writing the paper will increase, on average by 1 hour. D) For every 1.3 page increase in the length of the paper, the time spent writing the paper will increase, on average by 1 hour. E) The average time required to write a paper is 1.2 hours. F) The average time required to write a paper is 1.3 hours. 5. Which of the following statements about the y-intercept is incorrect in this context? A) The y-intercept has no logical interpretation, because it takes no time to write a paper with zero pages. B) The y-intercept is 1.3. C) The y-intercept indicates how much the time (hrs) required to write the paper changes, on average, as the length of the paper (pages) increases. D) The y-intercept is outside the range of the observed data. 6. Based on the plot and equation above, approximately how many hours would you predict that it would take to write a paper that is 10 pages in length? A) 5 B) 13 C) 20 D) 25 7. If someone wanted to use the regression equation above to predict how long it would take to complete a paper that is 40 pages in length, which of the following would be a correct response? A) Yes, you just need to plug 40 into the regression equation. B) Yes, the y-axis goes up to 40. C) No, 40 pages in length is outside the range of observed data. D) No, regardless of the number of pages, the regression results cannot be used for prediction. 8. The correlation between the two variables is 0.917 with a p-value of 0.0004. Based on that information, which of the following is the best and most complete description of the relationship between the variables? A) Strong, positive, linear, statistically significant B) Weak, positive, linear, statistically significant C) Strong, negative, linear, statistically significant D) Moderate, positive, linear, statistically significant E) Weak, negative, linear, statistically significant F) Strong, positive, linear, but not statistically significant G) Weak, positive, linear, but not statistically significant H) Strong, negative, linear, but not statistically significant I) Moderate, positive, linear, but not statistically significant J) Weak, negative, linear, but not statistically significant 9. If the point (x, y) = (25 pages, 38 hours) was removed from the regression plot above, the slope of the line would ____________. A) increase B) decrease C) remain the same 10. If the correlation between actual height and ideal height is 0.45 when those variables are measured in inches, the correlation will still be 0.45 if the variables are converted to centimeters. A) True B) False 11. A correlation of +0.3 is a stronger correlation than -0.7. A) True B) False 12. If a \"moderate\" relationship exists between two variables in a population, we would be more likely to detect a statistically significant relationship between the variables with a sample size of 40 than with a sample size of 400. A) True B) False 13. Researchers at Penn State University found a positive correlation between weight loss (pounds) and typical daily distance walked (miles) by Penn State students, so it can be concluded that walking leads to weight reduction. A) True B) False Use the information below for the first two questions that follow: A group of adults aged 20 to 80 years was tested to see how far away they could first hear a police siren that was coming toward them from behind. The regression equation that describes the relationship between distance (feet) and age of the person (year) was found to be: Distance = 500 - 3 Age 14. Which of the following statements about the regression analysis above is false? A) The slope is 3. B) The explanatory variable is Age. C) The response variable is Distance. D) The y-intercept is 500. 15. At what distance (ft) would a 50-year-old be predicted to first hear the police siren? A) 500 B) 50 C) 3 D) 150 E) 350 16. Consider the scatterplot below: Which of the fol- lowing best describes the correlation between x and y? A) positive B) negative C) zero D) cannot be determined from the plot Identify and explain how each of the following statements violates the definition and characteristics of correlation. 17. The correlation between the color of a person's left eye and right eye is 0.99. 18. The rankings for college football teams by the Coaches Poll and the AP Media Poll have a correlation of 1.17. 19. A study shows that there is a positive correlation between reading ability and shoe size for children between the ages 6 to 10 years. This result shows that an increase in shoe size is responsible for an increase in reading ability. A regression equation that describes the relationship between the amount of the bill ($) at a restaurant and the tip ($) that was left is: Tip = 2.9 + 0.1 Bill 20. Does the slope of the equation suggest that customers, on average, are tipping at least 15%? Why or why not? (Disregard the y-intercept in responding to this question.) 21. The correlation between these two variables is 0.586 and has a p-value of 0.127. Describe the relationship between the variables based on the correlation AND make a conclusion about the correlation based on the p-value