We consider linear predictor definitions of noncausality or strict exogeneity and show that it is restrictive to assert that there exists a time-invariant latent variable c such that x is strictly exogenous conditional on c. A restriction of this sort is necessary to justify standard techniques...

In data with a group structure, incidental parameters are included to control for missing variables. Applications include longitudinal data and sibling data. In general, the joint maximum likelihood estimator of the structural parameters is not consistent as the number of groups increases, with...

We examine the implications of arbitrage in a market with many assets. The absence of arbitrage opportunities implies that the linear functionals that give the mean and cost of a portfolio are continuous; hence there exist unique portfolios that represent these functionals. These portfolios span...

This paper reviews the literature on the relationship of economic growth to the education levels of the labor force. The emphasis is on Ben-Porath's contribution to some of the issues in this field: the endogeneity of schooling, the role of the public sector as an `absorber' of educated labor,...

This note reviews the history of the 'residual,' from its earliest articulation in Copeland (1937) to its codification in Solow (1957), describing the various earlier contributions by Tinbergen, Stigler, Schmookler, Fabricant, Kendrick, Abramovitz and others

R&D spillovers are, potentially, a major source of endogenous growth in various recent "New Growth Theory" models. This paper reviews the basic model of R&D spillovers and then focuses on the empirical evidence for their existence and magnitude. It reviews the older empirical literature with...

This survey reviews the growing use of patent data in economic analysis. After describing some of the main characteristics of patents and patent data, it focuses on the use of patents as an indicator of technological change. Cross-sectional and time-series studies of the relationship of patents...

This paper reviews the historical data on patenting in the United States with special reference to the last 20 years and their potential relation, if any, to the recent productivity slowdown. Two Points are made: Patents are not a "constant-yardstick" indicator of either inventive input or...

The paper describes the background for my original "hedonics" paper (Griliches 1961) and discusses some of the issues raised by the subsequent literature on this range of topics. It goes on to consider some of the implications of this work for the measurement of capital services and connects it...

The question I shall address in this pa-per is: Can the slowdown in productivity growth be explained, wholly or in part, by the recent slowdown in the growth of real R&D expenditures? But first we have to review the following questions: I) What is to be explained? Which productivity and what...