Margaritis Dimitris Margaritis & Fare Rolf Fare 
Market Power, Economic Efficiency And The Lerner Index [EPUB ebook] 

The book uses distance functions, a generalization of the more familiar production function, as the theoretical and empirical tools to construct Lerner indexes of market power in both the input and output markets. The use of distance functions enables us to explicitly account for the effects of firm inefficiency and price markups in the evaluation of market power. The book focusses on the theory and provides a menu of applications to construct measures of firm efficiency and market power in the financial and public sectors.