Consistent estimation in the bilinear multivariate errors-in-variables model

A bilinear multivariate errors-in-variables model is considered. It corresponds to an overdetermined set of linear equations AXB=C, A∈ℝ^m×n, B∈ℝ^p×q, in which the data A, B, C are perturbed by errors. The total least squares estimator is inconsistent in this case.  An adjusted least squares estimator is constructed, which converges to the true value X, as m →∞, q →∞. A small sample modification of the estimator is presented, which is more stable for small m and q and is asymptotically equivalent to the adjusted least squares estimator. The theoretical results are confirmed by a simulation study. Acknowledgements. We thank two anonymous reviewers for their suggestions and corrections.? A. Kukush is supported by a postdoctoral research fellowship of the Belgian office for Scientific, Technical and Cultural Affairs, promoting Scientific and Technical Collaboration with Central and Eastern Europe.? S. Van Huffel is a full professor with the Katholieke Universiteit Leuven.? I. Markovsky is a research assistant with the Katholieke Universiteit Leuven.? This paper presents research results of the Belgian Programme on Interuniversity Poles of Attraction (IUAP V-22), initiated by the Belgian State, Prime Minister's Office – Federal Office for Scientific, Technical and Cultural Affairs of the Concerted Research Action (GOA) projects of the Flemish Government MEFISTO-666 (Mathematical Engineering for Information and Communication Systems Technology), of the IDO/99/03 project (K.U. Leuven) “Predictive computer models for medical classification problems using patient data and expert knowledge”, of the FWO projects G.0078.01, G.0200.00, and G0.0270.02.? The scientific responsibility is assumed by its authors.     

Charity Technology Trust: a case study

Charity Technology Trust (CTT) is one of a new breed of philanthropic initiatives aimed at helping UK charities become more efficient by better use of technology. Its founder believes that charities are ideally placed to benefit from the reduced costs and shared benefits of jointly developed strategies and fundraising, communications and data management tools. CTT was formed to catalyse a move in this direction from the major UK fundraising charities and is supported by the personal philanthropic contributions of its trustees—a group of successful businessmen. The challenge for such a new organisation with a new idea is considerable, but after 18 months CTT is working with 27 of the top 100 UK charities on projects from online raffles through e‐mail communications to IT strategy. Copyright © 2003 Henry Stewart Publications     

Price Cap Regulation in the Cable Television Industry: Why was the Demand Stagnant?

During the period of 1992 to 1996, the cable television industry in the United States was regulated by the FCC, which took several price cap measures. As a result, the increase in the price cable service substantially slowed. However, the cable demand did not rise as anticipated. Using a model of imperfectly discriminating monopoly, the paper empirically investigates this curious phenomenon of stagnant demand despite lower prices. The paper finds that the FCC's price capping constrained both demand and prices. The demand was constrained since the price cap was designed to cover almost all TV channels carried by cable systems, and subsequently discouraged cable systems from meeting different customer preferences with multi-tier services.     

"Flexible" Work Practices and Occupational Safety and Health: Exploring the Relationship Between Cumulative Trauma Disorders and Workplace Transformation

This article matches establishment-level data on workplace transformation (e.g., quality circles, work teams, and just-in-time production) with measures of cumulative trauma disorders at these same establishments to explore the relationship between "flexible" workplace practices and workplace health and safety. The results reveal a positive, statistically significant, and quantitatively sizable relationship between cumulative trauma disorders and the use of quality circles and just-in-time production.     

Multiple Imputation in Multivariate Problems When the Imputation and Analysis Models Differ

Bayesian multiple imputation (MI) has become a highly useful paradigm for handling missing values in many settings. In this paper, I compare Bayesian MI with other methods – maximum likelihood, in particular—and point out some of its unique features. One key aspect of MI, the separation of the imputation phase from the analysis phase, can be advantageous in settings where the models underlying the two phases do not agree.     

Inferential Causal Models: Integrating Quality & Quantity

In-depth data analysis plus statistical modeling can produce inferentialcausal models. Their creation thus combines aspects of analysis by close inspection,that is, reason analysis and cross-tabular analysis, with statistical analysis procedures,especially those that are special cases of the generalized linear model (McCullaghand Nelder, 1989; Agresti, 1996; Lindsey, 1997). This paper explores some of the roots of this combined method and suggests some new directions. An exercise clarifies some limitations of classic reason analysis by showing how the cross tabulation of variables with controls for test factors may produce better inferences. Then, given the cross tabulation of several variables, by explicating Coleman effect parameters, logistic regressions, and Poisson log-linear models, it shows how generalized linear models provide appropriate measures of effects and tests of statistical significance. Finally, to address a weakness of reason analysis, a case-control design is proposed and an example is developed.     

Social Scientific Explanations?

Generally valid scientific explanations of observable social phenomena are still hardly available. By applying philosophical insights generated by Quine and derived from semiotics to social research methodology three kinds of context dependencies accompanying theory formation within social science are identified. The third context dependency is mostly not attended in theory formation about social phenomena thereby producing a ``connotation fallacy', which leaves almost all social theories undetermined and fallible. These context dependencies should be taken into account in the research design and be tested for using statistical criteria comprising a new methodology presented in this article.     

Regulating Banks through Market Discipline: A Survey of the Issues

Abstract.  The interest in the application of market discipline to regulate the financial industry has boomed recently due to the proposed New Capital Accord. This paper reviews the potential role market discipline can play in financial regulation. We start with a discussion of the rationale for financial regulation and with a brief history of the current regulatory mechanisms. Next, a definition of market discipline as a regulatory mechanism is advanced. We evaluate the disciplining power various market participants have. Finally, we argue that more external risk management disclosure is a condition sine qua non in order to enable market discipline as a regulatory mechanism. In this respect, the Basle Committee has taken the right approach.