At the time the study was conducted, the population of Lancaster was 48,027 while Glendora had 38,654 residents. Using prior probabilities based on these population figures and those given in Problem 11.11, and the entire lung function data set (with four AREA-defined groups), perform a discriminant function analysis on the fathers. Use FEV1 and FVC as classifying variables. Do you think the lung function measurements are useful in distinguishing among the four areas?