||The first volume of Franklin M. Fisher's collected essays, Industrial Organization, Economics, and the Law, focused on the application of economic analysis to legal disputes in the areas of regulation and antitrust. This second volume brings together Fisher's work in econometric theory and practice, including studies on the underlying structure of econometric models that were fundamental to the subject.Fisher's early discovery of block-recursive systems, together with his results on continuity for small specification errors, provided a foundation for all structural estimation. His later work on causation dealt with the implications of regarding simultaneous equation models as limiting cases of nonsimultaneous models. The essays in this book enlarge on those themes in various ways.Part one begins with essays that introduce the basic concepts of block-recursive systems and the foundational material for structural estimation in econometrics. They focus on simultaneous equations and the problem of exogenous variables, raising questions about the nature of econometric models and attempting to answer them through the analysis of block recursive models. Part two uses the results from Part one to examine issues of specification error and includes Fisher's classic exposition of Chow tests. Part three contains empirical I work, including studies of the copper industry, wheat supply in the nineteenth century, the famous Fisher-Griliches-Kaysen examination of the costs of automobile model changes, and the effect of the removal of firemen on railroad accidents.Franklin A Fisher is Professor of Economics at the Massachusetts Institute of Technology where John Monz is a Ph.D. candidate in economics.