The Pennsylvania State University University Park, PA 16802 Many metropolitan areas in the U.S. use statistical methods to predict concentrations of air quality parameters particularly O 3 .
Statistical methods offer a low cost approach to the air quality forecasting problem.
Typical statistical methods in use include multiple regression analysis and neural networking. The skill of statistical methods is due mainly to the strong correlation between O 3 concentrations and temperature as well as the high autocorrelation between daily O 3 peaks. Due to the strong dependence on temperature, regression based methods are unable to fully resolve the effect on O 3 levels of certain weather and transport conditions. As a result, forecasters in the region use the regression model as guidance with modification when necessary. Expert modification of the forecast increases overall skill with a median error of 9.0 ppbv and an rms error of 15.2 ppbv.