Qiying Wang  Peter C. B. Phillips 《Econometrica : journal of the Econometric Society》2009,77(6):1901-1948

Nonparametric estimation of a structural cointegrating regression model is studied. As in the standard linear cointegrating regression model, the regressor and the dependent variable are jointly dependent and contemporaneously correlated. In nonparametric estimation problems, joint dependence is known to be a major complication that affects identification, induces bias in conventional kernel estimates, and frequently leads to ill‐posed inverse problems. In functional cointegrating regressions where the regressor is an integrated or near‐integrated time series, it is shown here that inverse and ill‐posed inverse problems do not arise. Instead, simple nonparametric kernel estimation of a structural nonparametric cointegrating regression is consistent and the limit distribution theory is mixed normal, giving straightforward asymptotics that are useable in practical work. It is further shown that use of augmented regression, as is common in linear cointegration modeling to address endogeneity, does not lead to bias reduction in nonparametric regression, but there is an asymptotic gain in variance reduction. The results provide a convenient basis for inference in structural nonparametric regression with nonstationary time series when there is a single integrated or near‐integrated regressor. The methods may be applied to a range of empirical models where functional estimation of cointegrating relations is required.  相似文献   

    

Vittorio Addona  Masoud Asgharian  David B. Wolfson 《Revue canadienne de statistique》2009,37(2):206-218

For many diseases, logistic constraints render large incidence studies difficult to carry out. This becomes a drawback, particularly when a new study is needed each time the incidence rate is investigated in a new population. By carrying out a prevalent cohort study with follow‐up it is possible to estimate the incidence rate if it is constant. The authors derive the maximum likelihood estimator (MLE) of the overall incidence rate, λ, as well as age‐specific incidence rates, by exploiting the epidemiologic relationship, (prevalence odds) = (incidence rate) × (mean duration) (P/[1 ? P] = λ × µ). The authors establish the asymptotic distributions of the MLEs and provide approximate confidence intervals for the parameters. Moreover, the MLE of λ is asymptotically most efficient and is the natural estimator obtained by substituting the marginal maximum likelihood estimators for P and µ into P/[1 ? P] = λ × µ. Following‐up the subjects allows the authors to develop these widely applicable procedures. The authors apply their methods to data collected as part of the Canadian Study of Health and Ageing to estimate the incidence rate of dementia amongst elderly Canadians. The Canadian Journal of Statistics © 2009 Statistical Society of Canada  相似文献   

    

Sriram Narayanan  Ann S. Marucheck  Robert B. Handfield 《决策科学》2009,40(1):121-163

For nearly two decades, electronic data interchange (EDI) has been widely viewed as a technology pivotal to supply chain management that has also provided benefits to firms on multiple levels. Despite a substantial body of literature, there are a number of conflicting and inconclusive research results in this field. In this study, we synthesize the diverse body of research in EDI by organizing the literature into an initial theoretical framework. Based on a meta‐analysis of results from the empirical literature, we seek to clarify conflicting results from the literature in order to develop a more unified theoretical framework of contextual variables associated with EDI adoption factors and outcomes. From a managerial standpoint, our literature‐based framework offers a set of guidelines for making successful EDI adoption and implementation decisions.  相似文献   

    

Kathryn B. Laskey  Kenneth Laskey 《Wiley Interdisciplinary Reviews: Computational Statistics》2009,1(1):101-105

Service oriented architecture (SOA) is a paradigm for organizing a set of capabilities, often distributed across the network and possibly under the control of different ownership domains. The organized capabilities can be used to provide solutions to business problems. A business problem is broadly defined as any problem, in any domain of interest, encountered by an individual or organization as it goes about its business. SOA is applied to business problems that are amenable to information technology solutions. Services are made visible to potential users, interact with users through a series of information exchanges, and produce real‐world effects. Invocation and information exchange rely on standard languages and protocols that facilitate interoperability. From a user's perspective, invoking a service to produce an intended effect is experienced as a single, atomic operation. The detailed sequence of actions carried out by the service may involve any number of operations such as database queries, data transformations, execution of models, and formatting of displays. These operations may themselves be composed of lower level operations. The data and/or software modules required to perform the operations may reside at different physical locations and be controlled by different organizations. The details of composing the sequence of actions that produces the real world effect are transparent to the user interacting with the service. SOA frees users to concentrate on their business problem, leaving the details of the solution to the service. Copyright © 2009 John Wiley & Sons, Inc. This article is categorized under:

• Software for Computational Statistics > Software/Statistical Software

  相似文献   

    

Michael R. Greenberg  Marc Weiner  Gwendolyn B. Greenberg 《Risk analysis》2009,29(11):1578-1587

Every adult can eliminate the risk of losing control of personal health decisions and financial resources by having a last will and testament, health proxy, power of attorney, and living trust. Yet evidence suggests that less than a majority of adult Americans have these documents. We surveyed 900 adult Americans (25 plus years old) to determine what factors predict the possession of these risk-reducing documents. In total, 46% had a living will and testament, 32% a durable power of attorney, 30% a health proxy, and 18% a living trust. Events that prompt people with wealth to secure these documents, such as increasing age, getting married, having children, and experiencing a life-threatening event were the strongest predictors of having a will. These were also among the strongest predictors of having a health proxy, along with a personal history of being proactive, and a family history that fostered trust of attorneys. Affluence, age, and education were the strongest predictors of having a living trust, and the strongest correlate of having a durable power of attorney was having faced a life-threatening event, positive experiences with attorneys, and higher educational achievement.  相似文献   

    

Jeffrey J. Whicker  David R. Janecky  Ted B. Doerr 《Risk analysis》2008,28(5):1445-1456

Terrorist actions are aimed at maximizing harm (health, psychological, economical, and political) through the combined physical impacts of the act and fear. Immediate and effective response to a terrorist act is critical to limit human and environmental harm, effectively restore facility function, and maintain public confidence. Though there have been terrorist attacks in public facilities that we have learned from, overall our experiences in restoration of public facilities following a terrorist attack are limited. Restoration of public facilities following a release of a hazardous material is inherently far more complex than in industrial settings and has many unique technical, economic, social, and political challenges. For example, there may be a great need to quickly restore the facility to full operation and allow public access even though it was not designed for easy or rapid restoration, and critical information is needed for quantitative risk assessment and effective restoration must be anticipated to be incomplete and uncertain. Whereas present planning documents have substantial linearity in their organization, the “adaptive management” paradigm provides a constructive parallel paradigm for restoration of public facilities that anticipates and plans for uncertainty, inefficiencies, and stakeholder participation. Adaptive management grew out of the need to manage and restore natural resources in highly complex and changing environments with limited knowledge about causal relationships and responses to restoration actions. Similarities between natural resource management and restoration of a public facility after a terrorist attack suggest that integration of adaptive management principles explicitly into restoration processes will result in substantially enhanced and flexible responses necessary to meet the uncertainties of potential terrorist attacks.  相似文献   

    

Mylène Bédard  Jeffrey S. Rosenthal 《Revue canadienne de statistique》2008,36(4):483-503

The authors provide an overview of optimal scaling results for the Metropolis algorithm with Gaussian proposal distribution. They address in more depth the case of high‐dimensional target distributions formed of independent, but not identically distributed components. They attempt to give an intuitive explanation as to why the well‐known optimal acceptance rate of 0.234 is not always suitable. They show how to find the asymptotically optimal acceptance rate when needed, and they explain why it is sometimes necessary to turn to inhomogeneous proposal distributions. Their results are illustrated with a simple example.  相似文献   

    

J. C. W. Rayner  O. Thas  B. De Boeck 《Australian & New Zealand Journal of Statistics》2008,50(3):235-240

The Emerson (1968, Biometrics 24 , 695–701) recurrence relation has many important applications in statistics. However, the original derivation applied only to discrete distributions. In the following, a simple derivation is given that generalizes the Emerson recurrence relation to any distribution for which the necessary expectations exist. A modern application is outlined.  相似文献   

    

Michael H. Rothkopf  Andrew B. Whinston 《Production and Operations Management》2007,16(4):404-408

Electronic auctions have revolutionized procurement in the last decade. In many situations, they have replaced negotiations for supplier selection and price setting. While they have often greatly reduced transaction costs and increased competition, they have also encountered problems and resistance from suppliers resenting their intrusion on cooperative supplier/buyer relationships. In response to these issues, procurement auctions have evolved in radical new directions. Buyers use business rules to limit adverse changes. Some procurement auctions allow bidders to offer variants in the specifications of products to be supplied. Most important, some suppliers are allowing bidders to bid on packages of items, not just individual items. This tends to change procurement auctions from zero‐sum fights over supplier profit margins to win‐win searches for synergies. These changes have opened up many new research areas. Researchers are trying to improve how to deal with the computational issues involved in package auctions and to analyze the new auctions forms that are evolving. In general, equilibrium incentives are not known, and dealing with ties in package auctions is an issue. Computer scientists are analyzing the use of computerized bidding agents. Mechanisms that combine auctions with fixed buy prices or with negotiations need to be analyzed.  相似文献   

    

Christine B. Meyer  Ellen Altenborg 《英国管理杂志》2007,18(3):257-271

In the literature on M&A and social justice, equality is regarded as an important principle to facilitate social integration. This article debates what happens when the equality principle is operationalized; from intentions in the pre‐merger process to the distribution of resources and decision‐making rules in the post‐merger process. In a merger between two state‐owned telecoms corporations in the Scandinavian countries, we found that the principle of equality had the reverse effects on social integration to that predicted in the literature. Instead of facilitating the social integration process, the equality principle led to perceptual and structural fallacies negatively influencing social integration. We suggest that these disintegrating effects were particularly strong because this was an international merger between two state‐owned firms of unequal size.  相似文献