Question 2.70

2.70 Data generated by software

The following 20 observations on y and x were generated by a computer program.

y x y x
34.38 22.06 27.07 17.75
30.38 19.88 31.17 19.96
26.13 18.83 27.74 17.87
31.85 22.09 30.01 20.20
26.77 17.19 29.61 20.65
29.00 20.72 31.78 20.32
28.92 18.10 32.93 21.37
26.30 18.01 30.29 17.31
29.49 18.69 28.57 23.50
31.36 18.05 29.80 22.02
  1. Make a scatterplot and describe the relationship between y and x.
  2. Find the equation of the least-squares regression line and add the line to your plot.
  3. Plot the residuals versus x.
  4. What percent of the variability in y is explained by x?
  5. Summarize your analysis of these data in a short paragraph.