11.51 Predicting bone resorption using transformed variables. Refer to the previous exercise. Rerun using logs.

The following 11 exercises use the PCB data file. Polychlorinated biphenyls (PCBs) are a collection of synthetic compounds, called congeners, that are particularly toxic to fetuses and young children. Although PCBs are no longer produced in the United States, they are still found in the environment. Because human exposure to PCBs is primarily through the consumption of fish, the Environmental Protection Agency (EPA)

monitors the PCB levels in fish. Unfortunately, there are 209 different congeners, and measuring all of them in a fish specimen is an expensive and time-consuming process. You’ve been asked to see if the total amount of PCBs in a specimen can be estimated with only a few, easily quantifiable congeners. If this can be done, costs can be greatly reduced.