A consistent specification test for models defined by conditional moment restrictions

This article addresses statistical inference in models defined by conditional moment restrictions. Our motivation comes from two observations. First, generalized method of moments, which is the most popular methodology for statistical inference for these models, provides a unified methodology for statistical inference, but it yields inconsistent statistical procedures. Second, consistent specification testing for these models has abandoned a unified approach by regarding as unrelated parameter estimation and model checking. In this article, we provide a consistent specification test, which allows us to propose a simple unified methodology that yields consistent statistical procedures. Although the test enjoys optimality properties, the asymptotic distribution of the considered test statistic depends on the specific data generating process. Therefore, standard asymptotic inference procedures are not feasible. Nevertheless, we show that a simple original wild bootstrap procedure properly estimates the asymptotic null distribution of the test statistic

A CONSISTENT SPECIFICATION TEST FOR MODELS DEFINED BY CONDITIONAL MOMENT RESTRICTIONS

This article addresses statistical inference in models defined by conditional moment restrictions. Our motivation comes from two observations. First, generalized method of moments, which is the most popular methodology for statistical inference for these models, provides a unified methodology for statistical inference, but it yields inconsistent statistical procedures. Second, consistent specification testing for these models has abandoned a unified approach by regarding as unrelated parameter estimation and model checking. In this article, we provide a consistent specification test, which allows us to propose a simple unified methodology that yields consistent statistical procedures. Although the test enjoys optimality properties, the asymptotic distribution of the considered test statistic depends on the specific data generating process. Therefore, standard asymptotic inference procedures are not feasible. Nevertheless, we show that a simple original wild bootstrap procedure properly estimates the asymptotic null distribution of the test statistic.

A Consistent Test for the Martingale Difference Hypothesis

This paper considers testing that an economic time series follows a martingale difference process. The martingale difference hypothesis has been typically tested using information contained in the second moments of a process, that is, using test statistics based on the sample autocovariances or in the periodograms. Tests based on these statistics are inconsistent since they just test necessary conditions of the null hypothesis. In this paper we consider tests that are consistent against all fixed alternatives and against Pitman's local alternatives. Since the asymptotic distributions of the tests statistics depend on the data generating process, the tests are implemented using a modification of the wild bootstrap procedure. The paper justifies theoretically the proposed tests and examines their finite sample behavior by means of Monte Carlo experiments. In addition we include an application to exchange rate data.nonlinear dependence,nonparametric, correlation, bootstrap

Is this what the democratic city looks like? Local democracy, housing rights and homeownership in the Portuguese context

This article analyses the creation of a normative framework for the democratic city during the regime change in Portugal in 1975—the answers that were given to the question, ‘What should a city be like in a democratic regime?’ While I critically discuss post?democracy and its use of post?foundational contributions, I review the post?revolution Portuguese constitutional debate, contending that the call for democratization brought by urban popular organizations was answered with a political compromise that exchanged expectations of a participatory city for a commitment to a social rights city, enhanced with a promise of homeownership for urban popular segments. In light of this, in this article I question post?democratic proposals, arguing that when this approach implicitly establishes equivalence between democracy and ‘the political’, it has difficulties in interpreting how the grammar of democracy is ‘organized’ in conflictual and contingent processes of democratic institutionalization. As an alternative, I contend that a critical debate concerning democracy and the urban must address how democratic expectations of emancipation have been translated into institutions and rights through interwoven and situated processes of politicization and depoliticization that allow both politicization of the urban and the production of consent

The Pontificial Academy of St. Thomas Aquinas

A presentation of one of the most important Thomistic institutions, the Pontifical Academy of St. Thomas, founded by Pope Leo XIII in 1879, and renewed in 1999 by John Paul II. The article covers the origins of the project, its long history, and its recent reform

Pandemic influenza control in Europe and the constraints resulting from incoherent public health laws

© 2010 Martin et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Background: With the emergence of influenza H1N1v the world is facing its first 21st century global pandemic. Severe Acute Respiratory Syndrome (SARS) and avian influenza H5N1 prompted development of pandemic preparedness plans. National systems of public health law are essential for public health stewardship and for the implementation of public health policy[1]. International coherence will contribute to effective regional and global responses. However little research has been undertaken on how law works as a tool for disease control in Europe. With co-funding from the European Union, we investigated the extent to which laws across Europe support or constrain pandemic preparedness planning, and whether national differences are likely to constrain control efforts. Methods: We undertook a survey of national public health laws across 32 European states using a questionnaire designed around a disease scenario based on pandemic influenza. Questionnaire results were reviewed in workshops, analysing how differences between national laws might support or hinder regional responses to pandemic influenza. Respondents examined the impact of national laws on the movements of information, goods, services and people across borders in a time of pandemic, the capacity for surveillance, case detection, case management and community control, the deployment of strategies of prevention, containment, mitigation and recovery and the identification of commonalities and disconnects across states. Results: Results of this study show differences across Europe in the extent to which national pandemic policy and pandemic plans have been integrated with public health laws. We found significant differences in legislation and in the legitimacy of strategic plans. States differ in the range and the nature of intervention measures authorized by law, the extent to which borders could be closed to movement of persons and goods during a pandemic, and access to healthcare of non-resident persons. Some states propose use of emergency powers that might potentially override human rights protections while other states propose to limit interventions to those authorized by public health laws. Conclusion: These differences could create problems for European strategies if an evolving influenza pandemic results in more serious public health challenges or, indeed, if a novel disease other than influenza emerges with pandemic potential. There is insufficient understanding across Europe of the role and importance of law in pandemic planning. States need to build capacity in public health law to support disease prevention and control policies. Our research suggests that states would welcome further guidance from the EU on management of a pandemic, and guidance to assist in greater commonality of legal approaches across states.Peer reviewe

Composição centesimal da castanha-do-brasil (Bertholletia excelsa) comercializada em Macapá e Santana (AP).

O objetivo deste trabalho foi avaliar o valor nutritivo através da composição centesimal da amêndoa da castanha-do-brasil comercializada nas quatro principais feiras dos municípios de Macapá e Santana oriundas das reservas de Iratapuru, Cajari e Maracá