uBoost: A boosting method for producing uniform selection efficiencies from multivariate classifiers

The use of multivariate classifiers, especially neural networks and decision trees, has become commonplace in particle physics. Typically, a series of classifiers is trained rather than just one to enhance the performance; this is known as boosting. This paper presents a novel method of boosting that produces a uniform selection efficiency in a user-defined multivariate space. Such a technique is ideally suited for amplitude analyses or other situations where optimizing a single integrated figure of merit is not what is desired

Model selection for amplitude analysis

Model complexity in amplitude analyses is often a priori under-constrained since the underlying theory permits a large number of possible amplitudes to contribute to most physical processes. The use of an overly complex model results in reduced predictive power and worse resolution on unknown parameters of interest. Therefore, it is common to reduce the complexity by removing from consideration some subset of the allowed amplitudes. This paper studies a method for limiting model complexity from the data sample itself through regularization during regression in the context of a multivariate (Dalitz-plot) analysis. The regularization technique applied greatly improves the performance. An outline of how to obtain the significance of a resonance in a multivariate amplitude analysis is also provided

The World Bank and Governance

Summary The Bank's role in assisting developing countries improve their governance has been growing rapidly in recent years. Unlike bilateral donors, who increasingly are conditioning aid on civil and political rights and democracy, the Bank's concern, both operationally and in the country dialogue, is with the economic and social dimensions of governance. The article reviews the Bank's governance work and the issues that are in the areas of: public sector management (civil service reform, financial management, public enterprise reform and decentralization), the legal framework for development, participation, human rights, military expenditure and corruption. The article concludes with a section on the Bank's own governance, and describes some of the management changes now underway. RESUME La Banque mondiale et la gouvernance Le rôle que joue la Banque quand elle veut aider les pays en voie de développement à améliorer leur gouvernance a augmenté rapidement au cours des années recentes. A la différence des donateurs bilatéraux, qui imposent de plus en plus de conditions sur l'aide offerte au niveau des droits civils et politiques et de la démocratie, la participation de la Banque tant au niveau opérationnel qu'à celui du dialogue avec le pays concerné, s'adresserait plutôt aux dimensions économiques et sociales de la gouvernance. Dans leur article, les auteurs passent en revue les actions de la Banque dans le domaine de la gouvernance, ainsi que des questions qui se soulèvent dans certains domaines de la gestion du secteur public (réforme de l'Administration, gestion financière, réforme au sein de l'entreprise publique, décentralisation); le cadre juridique du développement; la participation; les droits de l'homme; la dépense militaire; et la corruption. L'article contient, en partie dernière, une section qui s'adresse à la gouvernance de la Banque elle?même, et décrit certains changements qui se produisent actuellement dans sa propre administration. RESUMEN El Banco Mundial y el gobierno En los últimos años, el Banco Mundial ha sido extendiendo su apoyo al processo de mejoramiento del gobierno en países en vías de desarrollo. Al revés de los donantes bilaterales, que condicionan su ayuda a la situación de los derechos civiles y políticos y de la democracia, el interés del Banco Mundial se centra en las dimensiones sociales y económicas del gobierno, tanto en el aspecto operacional como en el diálogo. El artículo reseña el trabajo del Banco en este campo, en las áreas de: manejo del sector público (reforma al servicio civil, manejo financiero, reforma de empresas públicas y descentralización), el marco legal para el desarrollo, participación, derechos humanos, gastos militares y corrupción. El artículo termina con una sección sobre el gobierno del propio Banco, y describe algunos de los cambios de manejo que se están llevando a cabo actualmente

Astronomical verification of a stabilized frequency reference transfer system for the Square Kilometre Array

In order to meet its cutting-edge scientific objectives, the Square Kilometre Array (SKA) telescope requires high-precision frequency references to be distributed to each of its antennas. The frequency references are distributed via fiber-optic links and must be actively stabilized to compensate for phase-noise imposed on the signals by environmental perturbations on the links. SKA engineering requirements demand that any proposed frequency reference distribution system be proved in "astronomical verification" tests. We present results of the astronomical verification of a stabilized frequency reference transfer system proposed for SKA-mid. The dual-receiver architecture of the Australia Telescope Compact Array was exploited to subtract the phase-noise of the sky signal from the data, allowing the phase-noise of observations performed using a standard frequency reference, as well as the stabilized frequency reference transfer system transmitting over 77 km of fiber-optic cable, to be directly compared. Results are presented for the fractional frequency stability and phase-drift of the stabilized frequency reference transfer system for celestial calibrator observations at 5 GHz and 25 GHz. These observations plus additional laboratory results for the transferred signal stability over a 166 km metropolitan fiber-optic link are used to show that the stabilized transfer system under test exceeds all SKA phase-stability requirements under a broad range of observing conditions. Furthermore, we have shown that alternative reference dissemination systems that use multiple synthesizers to supply reference signals to sub-sections of an array may limit the imaging capability of the telescope.Comment: 12 pages, accepted to The Astronomical Journa

Market mapping for improved cookstoves: barriers and opportunities in East Africa

The East African region has been a hub for the development and marketing of improved cookstoves from the 1980s. However, there are differences in the rates of uptake of stoves between Kenya, Uganda and Tanzania. To investigate, we use a participatory approach to market mapping, identifying the key barriers to market growth. Our findings illustrate common barriers of access to finance, but also differences between the countries in their stove value chains and enabling environments. Participatory use of market mapping techniques would help to catalyse further action at the national level. ABSTRACT: The East African region has been a hub for the development and marketing of improved cookstoves from the 1980s. However, there are differences in the rates of uptake of stoves between Kenya, Uganda and Tanzania. To investigate, we use a participatory approach to market mapping, identifying the key barriers to market growth. Our findings illustrate common barriers of access to finance, but also differences between the countries in their stove value chains and enabling environments. Participatory use of market mapping techniques would help to catalyse further action at the national level

Vegetation classification and mapping project report: Great Sand Dunes National Park and Preserve

NPS 140/101150.February 2010.Natural Resource Report NPS/ROMN/NRR--2010/179.Includes bibliographical references

Isotopic analysis of faunal material from South Uist, Western Isles, Scotland

This paper reports on the results from stable isotope analysis of faunal bone collagen from a number of Iron Age and later sites on the island of South Uist, in the Western Isles, Scotland. This preliminary investigation into the isotopic signatures of the fauna is part of a larger project to model the interaction between humans, animals, and the broader environment in the Western Isles. The results demonstrate that the island fauna data fall within the range of expected results for the UK, with the terrestrial herbivorous diets of cattle and sheep confi rmed. The isotopic composition for pigs suggests that some of these animals had an omnivorous diet, whilst a single red deer value might be suggestive of the consumption of marine foods, such as by grazing on seaweed. However, further analysis is needed in order to verify this anomalous isotopic ratio

The 3Mg trial: A randomised controlled trial of intravenous or nebulised magnesium sulphate versus placebo in adults with acute severe asthma

Background: Magnesium sulphate, administered by the intravenous (i.v.) or inhaled (nebulised) route, has been proposed as a treatment for adults with acute severe asthma. Existing trials show mixed results and uncertain evidence of benefit. Objectives: We aimed to determine whether i.v. or nebulised magnesium sulphate improves symptoms of breathlessness and reduces the need for hospital admission in adults with acute severe asthma. Design: Multicentre, double-blind, placebo-controlled, three-arm, randomised trial. Setting: The emergency departments of 34 acute hospitals in the UK. Participants: We recruited 1109 adults (age > 16 years) with acute severe asthma [peak expiratory flow rate (PEFR) 25 breaths per minute, heart rate > 110 beats per minute or inability to complete sentences in one breath]. Patients with life-threatening features or a contraindication to either nebulised or intravenous magnesium sulphate were excluded. Interventions: Participants were randomly allocated to i.v. magnesium sulphate (2 g over 20 minutes) or nebulised magnesium sulphate (3 × 500 mg over 1 hour) or standard therapy alone. Main outcome measures: The primary outcome was the proportion of patients admitted to hospital (either after emergency department treatment or at any time over the subsequent 7 days) and breathlessness measured on a 100-mm visual analogue scale (VAS) over 2 hours after initiation of treatment. Results: We randomised 406 patients to i.v. magnesium sulphate, 339 to nebulised magnesium sulphate and 364 to placebo. Hospital admission was recorded for 394, 332 and 358 patients, respectively, and VAS breathlessness for 357, 296 and 323 patients respectively. Mean age was 36.1 years and 763 out of 1084 (70%) patients were female. Intravenous magnesium sulphate was associated with an odds ratio (OR) of 0.73 [95% confidence interval (CI) 0.51 to 1.04; p = 0.083] for hospital admission, an improvement in VAS breathlessness that was 2.6mm (95% CI -1.6 to 6.8 mm; p = 0.231) greater than that associated with placebo and an improvement in PEFR that was 2.4 l/minute (95% CI -8.8 to 13.6 l/minute; p = 0.680) greater than that associated with placebo. Nebulised magnesium sulphate was associated with an OR of 0.96 (95% CI 0.65 to 1.40; p = 0.819) for hospital admission, an improvement in VAS breathlessness that was 2.6mm (95% CI -1.8mm to 7.0 mm; p = 0.253) less than that associated with placebo and an improvement in PEFR that was 2.6 l/minute (95% CI -9.2 to 14.5 l/minute; p = 0.644) less than that associated with placebo. There were no significant differences between i.v. or nebulised magnesium sulphate and placebo for any other outcomes. The number (%) of patients reporting any side effect was 61 (15.5%) in the i.v. group, 52 (15.7%) in the nebuliser group and 36 (10.1%) in the placebo group. The ORs for suffering any side effect were 1.68 (95% CI 1.07 to 2.63; p = 0.025) for i.v. compared with placebo and 1.67 (95% CI 1.05 to 2.66; p = 0.031) for nebuliser compared with placebo. Conclusions: We were unable to demonstrate a clinically worthwhile benefit from magnesium sulphate in acute severe asthma. There was some weak evidence of an effect of i.v. magnesium sulphate on hospital admission, but no evidence of an effect on VAS breathlessness or PEFR compared with placebo. We found no evidence that nebulised magnesium sulphate was more effective than placebo. Trial registration: Current Controlled Trials ISRCTN04417063. Source of funding: This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 18, No. 22. See the NIHR Journals Library programme website for further project information. © Queen's Printer and Controller of HMSO 2014