Body size and wages in Europe: A semi-parametric analysis

Evidence of the association between wages and body size –typically measured by the body mass index– appears to be sensitive to estimation methods and samples, and varies across gender and ethnic groups. One factor that may contribute to this sensitivity is the non-linearity of the relationship. This paper analyzes data from the European Community Household Panel survey and uses semi-parametric techniques to avoid functional form assumptions and assess the relevance of standard models. If a linear model for women and a quadratic model for men fit the data relatively well, they are not entirely satisfactory and are statistically rejected in favour of semiparametric models which identify patterns that none of the parametric specifications capture. Furthermore, when we use height and weight in the models directly, rather than equating body size with the body mass index, the semi-parametric models reveal a more complex picture with height having additional effects on wages. We interpret our results as consistent with the existence of a wage premium for physical attractiveness rather than a penalty for unhealthy weight.