Question 11: The diagonal elements ofhat matrix. also referred to as the hat values or leverage values, measures the inuence of observation '1 on the regression line when removing observation 1. a. True b. False Question 12: In a regression study. a 95% confidence interval for [31 was given as: (52). What does this confidence interval mean? a. The interval (52) contains the true [31 with 95% probability b. 95% of all possible [31's are in(512) c. 95% of the interval (52) contains the true [31 d. [f we were to repeat. the experiment many times [i.e.. repeatedly take a new sample ofsize n and compute the same confidence interval], roughly 95% of the generated intervals would contain the true [31 Question 13: In a regression study. a 95% confidence interval for [31 was given as: (52). Which of following is correct? a. The 90% interval will be wider than the 95% interval b. The 99% interval will be wider than the 95% interval Question 14: In simple linear regression. the confidence interval for the mean response is always narrowest. around X a. True b. False 30 25 A 20 > 15 10 ... 5 0 10 15 X a. High influential point of the regression line b. High leverage point