A Test for the Presence of Central Bank Intervention in the Foreign Exchange Market With an Application to the Bank of Canada

We propose a general non-linear simultaneous equations framework for the econometric analysis of models of intervention in foreign exchange markets by central banks in response to deviations of exchange rates from target levels. We consider the instrumental variables estimation of possibly non-linear response functions and tests of intervention when the functional form may be non-linear, asymmetric, and may contain unknown shape parameters. The methodology applies techniques developed for testing in the presence of nuisance parameters unidentified under a null hypothesis to a nonlinear simultaneous equations model. We report the results of an empirical analysis of activity of the Bank of Canada, for the period from 1953-2006, with regard to the Canada-U.S. exchange rate, with changes in foreign reserves proxying for intervention activity. Nous proposons un cadre de référence général pour les équations non-linéaires simultanées s’appliquant à l’analyse économétrique de modèles d’intervention des banques centrales dans les marchés des devises étrangères, en réponse aux écarts des taux de change par rapport aux niveaux cibles. Nous prenons en considération l’estimation des variables instrumentales liées aux fonctions de réponses possiblement non-linéaires et aux tests en matière d’interventions lorsque la forme fonctionnelle peut être non linéaire, asymétrique et lorsqu’elle peut contenir des paramètres de forme inconnue. La méthodologie applique, à un modèle à équations simultanées non linéaires, des techniques élaborées pour effectuer des tests en présence de paramètres de nuisance non identifiés sous une hypothèse nulle. Nous présentons les résultats d’une analyse empirique des activités de la Banque du Canada, durant la période de 1953-2006, relativement au taux de change Canada-É.-U., les variations des réserves étrangères permettant les activités d’intervention.unidentified nuisance parameter, nonlinear simultaneous equations, foreign exchange reserves, policy reaction functions, paramètre de nuisance non identifié, équations simultanées non linéaires, réserves de change, fonctions de réaction de la politique

Foreword: Making Sense of Information for Environmental Protection

Despite the ubiquity of information, no one has proposed calling the present era the Knowledge Age. Knowledge depends not only on access to reliable information, but also on sound judgment regarding which information to access and how to situate that information in relation to the values and purposes that comprise the individual\u27s or the social group\u27s larger projects. This is certainly the case for wise and effective environmental governance. A regulator needs accurate information to understand the nature of a problem and the consequences of potential responses. Likewise, the regulated community needs information to decide how best to comply with adopted rules, and the public needs information in order to accept the credibility and legitimacy of the regulatory regime. But governance also requires judgment regarding how to manage information itself - how to structure burdens of proof in light of goals such as public safety or promotion of economic growth, how to balance the public\u27s interest in disclosure against competing aims such as national security or the protection of trade secrets, whether to withhold information in the belief that it may actually be harmful to the recipient, and so on. This paper, written as a foreword for the Texas Law Review\u27s symposium issue, Harnessing the Power of Information for the Next Generation of Environmental Law, provides a model to understand the role of information in environmental law - how it is generated, utilized, and disseminated within regulatory processes. Drawing on the diverse and significant insights of the symposium articles, the paper attempts both to make sense of the role of information in environmental protection and to highlight significant questions and concerns

Ultradense, Deep Subwavelength Nanowire Array Photovoltaics As Engineered Optical Thin Films

A photovoltaic device comprised of an array of 20 nm wide, 32 nm pitch array of silicon nanowires is modeled as an optical material. The nanowire array (NWA) has characteristic device features that are deep in the subwavelength regime for light, which permits a number of simplifying approximations. Using photocurrent measurements as a probe of the absorptance, we show that the NWA optical properties can be accurately modeled with rigorous coupled-wave analysis. The densely structured NWAs behave as homogeneous birefringent materials into the ultraviolet with effective optical properties that are accurately modeled using the dielectric functions of bulk Si and SiO_2, coupled with a physical model for the NWA derived from ellipsometry and transmission electron microscopy

The case of Heinrich Wilhelm Poll (1877-1939): A German-Jewish geneticist, eugenicist, twin researcher, and victim of the Nazis

This paper uses a reconstruction of the life and career of Heinrich Poll as a window into developments and professional relationships in the biological sciences in Germany in the period from the beginning of the twentieth century to the Nazi seizure of power in 1933. Poll's intellectual work involved an early transition from morphometric physical anthropology to comparative evolutionary studies, and also found expression in twin research - a field in which he was an acknowledged early pioneer. His advocacy of eugenics led to participation in state-sponsored committees convened to advise on social policy, one of which debated sterilisation and made recommendations that led eventually to the establishment of the notorious Kaiser Wilhelm Institute for Anthropology, Human Heredity and Eugenics. However, his status as a prominent geneticist and, in particular, as a eugenicist had an ironic and ultimately tragic dimension. Heinrich Poll was of Jewish birth, and this resulted in his career being destroyed by an application of the population policies he had helped put in place