Physical exercise and social inequality in Norway–A comparison of OLS and quantile regression analysis

Abstract

About two thirds of the Norwegian population exercise less than recommended by public authorities. Traditional studies of exercise and social inequality using OLS-regression give us information on the average person (conditioned mean value of a distribution), but might ignore information useful for understanding the situation for those, as in the Norwegian case, less physically active. In this article quantile regression–addressing units at various quantiles, not only the mean–is used to study social inequality related to physical exercise. Three types of exercise are studied–exercising locally, associational sport, fitness exercise–in light of social background variables. The crux of the analyses is an understanding of how the dependence of various independent variables differs across quantiles and that these results in several cases also differ from what OLS-regression tells us. The data applied are Norwegian (ISSP 2007).