Researchers at General Motors collected data on 60 U.S. Standard Metropolitan Statistical Areas (SMSA's) in a study of whether air pollution contributes to mortality. The dependent variable for analysis is age adjusted mortality (called "Mortality"). The data include variables measuring demographic characteristics of the cities, variables measuring climate characteristics, and variables recording the pollution potential of three different air pollutants.
The pollution variables are highly skewed. A logarithm transformation makes them much more nearly symmetric. Various multiple regression models may be used to determine whether air pollution is significantly related to mortality.