In this paper we provide a methodology that jointly studies production and demand for multi-product firms using detailed firm-product level data from Denmark. We estimate marginal cost by combining production function estimation with a cost function that allows for quasi-fixed inputs. We use a...

Abstract U.S. firms have reduced their investment in scientific research ("R") compared to product development ("D"), raising questions about the returns to each type of investment, and about the reasons for this shift. We use Census data that disaggregates "R" from "D" to study how US firms...