Annual measurements of the number of powerboat registrations (in thousands) and the number of manatees killed by powerboats in Florida were collected over the 14 years 1977-1990. A scatterplot of the data, least squares regression line, and correlation coefficient follow.
-The year 1984 had 559,000 powerboat registrations and 34 manatee deaths. Did the least squares regression line underestimate, overestimate, or accurately estimate the number of manatee deaths for the year 1984?
A) Underestimate
B) Overestimate
C) Accurately estimate

Question

Annual measurements of the number of powerboat registrations (in thousands) and the number of manatees killed by powerboats in Florida were collected over the 14 years 1977-1990. A scatterplot of the data, least squares regression line, and correlation coefficient follow. 
-The year 1984 had 559,000 powerboat registrations and 34 manatee deaths. Did the least squares regression line underestimate, overestimate, or accurately estimate the number of manatee deaths for the year 1984?
A) Underestimate 
B) Overestimate 
C) Accurately estimate

Quizplus · Accepted Answer

The least squares regression line typically underestimates when the actual data point is above the line, which is likely the case here given the high number of powerboat registrations and manatee deaths.

Annual Measurements of the Number of Powerboat Registrations (In Thousands)