Product differentiation and systematic risk: theory and empirical evidence

Firms producing differentiated products have high margins and therefore low risk. As a result firms invest more into developing differentiated products when they perceive risk is high. Higher risk also implies higher product skewness towards more differentiated products and therefore higher average markups. The model predicts endogenous systematic and idiosyncratic riskiness as well as endogenous intensity of competition: firms in high risk industries reduce their riskiness by competing less than firms in low risk industries. Empirical evidence on product differentiation, R\&D expenses, B/M ratios, and market $\beta$ is consistent with the model.