Problem: Sisters and brothers. How strongly do physical characteristics of sisters and brothers correlate? Here are data on the heights (in inches) of 12 adult pairs:12
|
Brother
|
71
|
68
|
66
|
67
|
70
|
71
|
70
|
73
|
72
|
65
|
66
|
70
|
|
Sister
|
69
|
64
|
65
|
63
|
65
|
62
|
65
|
64
|
66
|
59
|
62
|
64
|
(a) Use your calculator or software to find the correlation and the equation of the least-squares line for predicting sister's height from brother's height. Make a scatterplot of the data and add the regression line to your plot.
(b) Damien is 70 inches tall. Predict the height of his sister Tonya. Based on the scatterplot and the correlation r, do you expect your prediction to be very accurate? Why?