Sisters and brothers (3.1, 3.2) How strongly do physical characteristics of sisters and brothers correlate? Here are data on the heights (in inches) of 11 adult pairs:8 Brother: 71 68 66 67 70 71 70 73 72 65 66 Sister: 69 64 65 63 65 62 65 64 66 59 62

(a) Construct a scatterplot using brother’s height as the explanatory variable. Describe what you see.

(b) Use your calculator to compute the least-squares regression line for predicting sister’s height from brother’s height. Interpret the slope in context.

(c) Damien is 70 inches tall. Predict the height of his sister Tonya.

(d) Do you expect your prediction in

(c) to be very accurate?
Give appropriate evidence to support your answer.