Stats teachers’ cars A random sample of AP® Statistics teachers was asked to report the age (in years)

and mileage of their primary vehicles. A scatterplot of the data, a least-squares regression printout, and a residual plot are provided below.

Predictor Coef SE Coef T P Constant 3704 8268 0.45 0.662 Age 12188 1492 8.17 0.000 S = 20870.5 R-Sq = 83.7% R-Sq(adj) = 82.4%

(a) Give the equation of the least-squares regression line for these data. Identify any variables you use.

(b) One teacher reported that her 6-year-old car had 65,000 miles on it. Find and interpret its residual.

(c) What’s the correlation between car age and mileage?
Interpret this value in context.

(d) Is a linear model appropriate for these data? Explain how you know.

(e) Interpret the values of s and r2.

Transcribed Image Text:

Residual Mileage 160,000 140,000- 120,000- 100,000- 80,000- 60,000 40,000 20,000 60,000 50,000 40,000 30,000 20,000 10,000 0 0 0 2 4 6 8 10 -10,000 -20,000 -30,000 0 2 4 6 Age Age 00 8 10 12 12 22