As an alternative to the use of father’s height to predict son’s height, Gallon also used the midparent height, the average of the father’s and mother’s heights. Here are the heights of nine female students along with their midparent heights in inches: Midparent 66.0 65.5 71.5 68.0 70.0 65.5 67.0
Daughter 64.0 63.0 69.0 69.0 69.0 65.0 63.0
Midparent 70.5 69.5 64.5 67.5
Daughter 68.5 69.0 64.0 67.0
a. Make a scatter plot of daughter’s height against the midparent height and comment on the strength of the relationship.
b. Is the daughter’s height completely and uniquely determined by the midparent height? Explain.
c. Use the accompanying MINITAB output to obtain the equation of the least squares line for predicting daughter height from midparent height and then predict the height of a daughter whose midparent height is 70 inches. Would you feel comfortable using the least squares line to predict daughter height when midparent height is 74 inches? Explain.