Question

Questions 18-19: We want to use an alligator’s length (in feet) to predict its weight (in pounds). A linear regression model is fit and is y = 10 + 41x. 18. An alligator that is 10 feet long actually weighs 403 pounds. Calculate that alligator’s residual: *

(A) –17 (B) –0.41 (C) 0.41 (D) 9.59 (E) 17

19. Choose the best interpretation of the slope: *

(A) An alligator that is 0 feet long, on average, will weigh 10 pounds. (B) For every additional 41 pounds in weight, an alligator’s length is expected to increase on average by 10 feet. (C) An alligator 8 feet long is expected to be about 41 pounds heavier than a 7-foot alligator. (D) For every additional foot in length, an alligator is expected to weight 41 less pounds on average. (E) The slope has no practical interpretation in this problem.

Answer 1

18)

since residual =actual value-predicted value =403-(10+41*10) = -17

option A is correct

19) option D should be 41 more pounds in place of 41 less pounds since coefficient of slope is postiive)(please check with your instructor )

herer slope is :  For every additional foot in length, an alligator is expected to weight 41   pounds more on average.