This paper describes the construction of a large panel data set covering about 2600 firms in the U.S. manufacturing sector for up to twenty years which contains annual data on financial variables, employment, research and development expenditures, and aggregate patent applications. This data set...

This paper investigates the relationship between earnings, schooling, and ability for young men and women who entered the labor force during the late 60s and 70s. The emphasis is on controlling for both observed and unobserved family characteristics, extending a framework developed earlier by...

As patent data become more available in machine-readable form, an increasing number of researchers have begun to use measures based on patents and their citations as indicators of technological output and information flow. This paper explores the economic meaning of these citation-based patent...

This paper describes the database on U.S. patents that we have developed over the past decade, with the goal of making it widely accessible for research. We present main trends in U. S. patenting over the last 30 years, including a variety of original measures constructed with citation data,...

This paper focuses on developing and adapting statistical models of counts (non-negative integers) in the context of panel data and using them to analyze the relationship between patents and R&D expenditures. The model used is an application and generalization of the Poisson distribution to...

It is known that innovations in the market value of manufacturing firms and their RhD expenditures are related (Pakes (1985) and Mairesse and Siu (1984)). This could be due to shifts in the demand for the output of a particular firm, to shifts in the technological opportunities available to the...

This paper extends earlier work on the R&D to patents relationship (Pakes-Griliches 1980, and Hausman, Hall, and Griliches, 1984) to a larger but shorter panel of firms. Using both non-linear least squares and Poisson type models to treat the problem of discreteness in the dependent variable the...

This paper summarizes a number of studies which use patent data to examine different aspects of technological change. It describes our firm level data set construction effort; reports on the relationship between RLD expenditures and the level of patenting; analyzes the relationship between...