Economics Research Works

Permanent URI for this collectionhttp://hdl.handle.net/1903/9

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Start date: 2013End date: 2019

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Now showing 1 - 6 of 6
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    Uniform Inference in Panel Autoregression
    (MDPI, 2019-11-26) Chao, John C.; Phillips, Peter C. B.
    This paper considers estimation and inference concerning the autoregressive coefficient (𝜌) in a panel autoregression for which the degree of persistence in the time dimension is unknown. Our main objective is to construct confidence intervals for 𝜌 that are asymptotically valid, having asymptotic coverage probability at least that of the nominal level uniformly over the parameter space. The starting point for our confidence procedure is the estimating equation of the Anderson–Hsiao (AH) IV procedure. It is well known that the AH IV estimation suffers from weak instrumentation when 𝜌 is near unity. But it is not so well known that AH IV estimation is still consistent when 𝜌=1. In fact, the AH estimating equation is very well-centered and is an unbiased estimating equation in the sense of Durbin (1960), a feature that is especially useful in confidence interval construction. We show that a properly normalized statistic based on the AH estimating equation, which we call the 𝕄 statistic, is uniformly convergent and can be inverted to obtain asymptotically valid interval estimates. To further improve the informativeness of our confidence procedure in the unit root and near unit root regions and to alleviate the problem that the AH procedure has greater variation in these regions, we use information from unit root pretesting to select among alternative confidence intervals. Two sequential tests are used to assess how close 𝜌 is to unity, and different intervals are applied depending on whether the test results indicate 𝜌 to be near or far away from unity. When 𝜌 is relatively close to unity, our procedure activates intervals whose width shrinks to zero at a faster rate than that of the confidence interval based on the 𝕄 statistic. Only when both of our unit root tests reject the null hypothesis does our procedure turn to the 𝕄 statistic interval, whose width has the optimal 𝑁−1/2𝑇−1/2 rate of shrinkage when the underlying process is stable. Our asymptotic analysis shows this pretest-based confidence procedure to have coverage probability that is at least the nominal level in large samples uniformly over the parameter space. Simulations confirm that the proposed interval estimation methods perform well in finite samples and are easy to implement in practice. A supplement to the paper provides an extensive set of new results on the asymptotic behavior of panel IV estimators in weak instrument settings.
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    Burst of Fall, A Painting by Alma Thomas
    (2019-01) Almon, Clopper
    "Burst of Fall" is a 1968 painting by the Alma W. Thomas, and African-American woman painter of the Washington Color school. This brief note describes the circumstances of its origin and of its initial purchase. It includes as jpg image of the painting.
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    The Gwx Story
    (www.CreateSpace.com, 2017) Almon, Clopper
    This is the story in tutorial form of the creation of a program, Gwx, for building economic models, both macroeconomic and multisectoral. The program closely resembles the G7 program. Like G7, it is written in C++ but it is built with free, open-source, cross-platform tools. There are many books about how to use some specific computer program but few about what was going on in the mind of the designer and programmer as the project evolved, as problems emerged and were solve. This is such a book. The program, Gwx, is designed to be used with the author's book, The Craft of Economic Modeling.
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    The Craft of Economic Modeling
    (www.CreateSpace.com, 2017) Almon, Clopper
    This book is a practical guide to building economic models, both macroeconomic and multisectoral. It uses free software available from the Internet together with regularly updated databanks including the quarterly national accounts of the United States. It does NOT deal with some recent fads in economic model building, such as Real Business Cycles, Computable General Equilibriium models, nor DSGE models, all of which are, in the author's opinion, "alternative reality" models at best.
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    Inforum Models: Origin, Evolution, and By-ways Avoided
    (Institute of Economic Forecasting, Russian Academy of Sciences, 2015) Almon, Clopper
    Inforum models combine input-output tables with econometric analysis in dynamic models in which the investment in each industry depends upon the growth of output in that industry. They have been built and used in a number of countries including the USA, Russia, Germany, Poland, Latvia, Austria, Italy, Spain, the United Kingdom, South Africa, Mexico, Colombia, China, Japan, Taiwan, Thailand, and Vietnam and perhaps others. They make extensive use of econometrics and input-output analysis to describe the functioning of an economy not only at a macroeconomic level but also at the level of individual products and industries. This paper records – somewhat autobiographically on the part of the author -- the beginnings of these models, outlines their evolution, defends them and other econometric models against the sweeping Lucas critique, and mentions some of the fads in economics and modeling which have been avoided for good reason.
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    Velia and the Cilento, an Introduction
    (2013) Almon, Clopper
    Material for students in a Study Abroad course beginning in Ascea, near Velia, in Southern Italy. It begins with the geological evolution of the Mediterranean and moves on to the prehistory of the area, the coming of the Greeks, the settlement of Elea = Velia, the Eleatic philosophers, the area in Roman times, and history up to the present, with special attention to the Consorzio Velia, which provides water to the area.