A Fixed-b Perspective on the Phillips-Perron Unit Root Tests

We extend fixed-b asymptotic theory to the nonparametric Phillips-Perron (PP) unit root tests. We show that the fixed-b limits depend on nuisance parameters in a complicated way. These non-pivotal limits provide an alternative theoretical explanation for the well known finite sample problems of PP tests. We also show that the fixed-b limits depend on whether deterministic trends are removed using one-step or two-step approaches, contrasting the asymptotic equivalence of the one- and two-step approaches under a consistency approximation for the long run variance estimator. Based on these results we introduce modified PP tests that allow for fixed-b inference. The theoretical analysis is cast in the framework of near-integrated processes which allows to study the asymptotic behavior both under the unit root null hypothesis as well as for local alternatives. The performance of the original and modified tests is compared by means of local asymptotic power and a small simulation study.Nonparametric kernel estimator, long run variance, detrending, one-step, two-step

Integrated Modified OLS Estimation and Fixed-b Inference for Cointegrating Regressions

This paper is concerned with parameter estimation and inference in a cointegrating regression, where as usual endogenous regressors as well as serially correlated errors are considered. We propose a simple, new estimation method based on an augmented partial sum (integration) transformation of the regression model. The new estimator is labeled Integrated Modified Ordinary Least Squares (IM-OLS). IM-OLS is similar in spirit to the fully modified approach of Phillips and Hansen (1990) with the key difference that IM-OLS does not require estimation of long run variance matrices and avoids the need to choose tuning parameters (kernels, bandwidths, lags). Inference does require that a long run variance be scaled out, and we propose traditional and fixed-b methods for obtaining critical values for test statistics. The properties of IM-OLS are analyzed using asymptotic theory and finite sample simulations. IM-OLS performs well relative to other approaches in the literature.Bandwidth, cointegration, fixed-b asymptotics, Fully Modified OLS, IM-OLS, kernel

Leadership Solutions for a For-Profit Secondary School in Vietnam

The opportunity to attend a university and pursue higher education is a dream that is shared by many high school students and their parents all over the world. Students from developing countries have long studied in the west, but the number of students from developing counties that hope to study in the west has risen considerably in recent years. However, there is often a significant difference in the secondary curriculum in developing countries and the secondary curriculum in western countries which can cause difficulties for students that are new to a more western oriented education. In response to this situation many developing countries have seen an increase in privately owned schools that aim to prepare local students at the secondary level for academic success in western universities. However, many local investors face numerous difficulties in establishing a secondary school with a western curriculum in their countries (Vietnam, 2007). One school that is attempting to face these challenges and provide a western secondary curriculum to local students that hope to study in the west is School X (name changed)

Air Force Materiel Command (AFMC) Modeling, Simulation, and Analysis (MS&A) Interactive Database

This study develops a high level, unifying taxonomy for Modeling, Simulation, and Analysis (MS&A) products for the Air Force Materiel Command (AFMC). AFMC is concerned that limited resources are being expended on duplicative MS&A efforts. No mechanism exists that would confirm or deny this concern, so it was suggested that a database could be developed to catalog and track AFMC\u27s MS&A inventory. First, it was necessary to determine the information that a decision maker needs to select a suitable MS&A product. Potential traits and characteristics were identified through review of current regulatory guidance, interviews with MS&A users, and a study of the current literature. Using the collected information, a survey was developed and distributed to 40 members of the Modeling and Simulation Technical Planning Integrated Product Team (M&S TPIPT). Survey results provided the foundation for developing a limited prototype database. This prototype was tested to ascertain the retrieval performance of the cataloging system. The test results failed to confirm the retrieval capability, but the test participants believed that cataloging AFMC\u27s MS&A inventory would have great benefit

DEVELOPMENT & INTEGRATION OF FHIR WITH OPEN-SOURCE EMR & RELATIONAL DATABASES

This project looks into the development and implementation of an open source EHR software, using a FHIR interface to the system for data exchange. The EMR system used was OpenEMR, which is an open source EMR system that uses MySQL as the database backend combined with Apache and PHP to provide a user interface. The FHIR interface uses HAPI-FHIR which is an open source framework and libraries available for JAVA. Using JAVA, a RESTful API is created in order to respond to requests, and to also receive FHIR messages using the information stored in the two SQL databases, OpenEMR database and the FHIR database

Supporting Refugee Children in Pennsylvania Public Schools

This study documented the lived experiences of professionals with significant background working with child refugees, in an attempt to understand how practitioners view the information, resources, and other supports required to assure child refugees’ successful physical, cognitive, social, and emotional development. An extensive review of the published research on child refugees in the Unitd States described specific international treaties, federal statutes, and state codes, addressed developmental disruptions as refugee children experience them, and explored the school experience of specific refugee cultural groups, yet revealed few reports of practitioners’ perspectives. Accordingly, this investigation sought the views of ten school and community professionals who engage with child refugees in a medium-sized, suburban school district to determine 1) What advice would they offer to those who will serve refugee children in public schools? 2) How useful do they find background information on legal mandates and the refugee child’s experience prior to resettlement, and when is this information most beneficial? 3) How do they experience a child refugee’s developmental disruptions, and how do they prioritize work on these disruptions? A one hour semi-structured interview addressed knowledge, skills, and practices that professionals found to be successful when working with a refugee population, along with barriers that they encountered. A three-part, twenty-six item follow-up survey asked participants to provide background information on their experiences, rate their knowledge of federal and state legal mandates and refugee cultural experiences (e.g., home country context, refugee camp conditions), and identify any developmental disruptions a refugee child presented in their setting. Participants reported successes and barriers that were largely role specific. Several themes, however, arose across all interviews. These themes included: 1) addressing students’ language needs, 2) engaging community resources, 3) addressing school needs related to cultural context education, 4) building relational trust, 5) identifying and addressing bullying, and 6) collaborating in pursuit of common professional goals. In addition, interviewees identified motivation and transformation as personal experiences in their work with child refugees. Findings lead to three implications, including development of comprehensive and specific state policy, recommendations for professional standards of practice, and revision to pre-service teacher and school leader curricula

Nonparametric Rank Tests for Non-stationary Panels

This study develops new rank tests for panels that include panel unit root tests as a special case. The tests are unusual in that they can accommodate very general forms of both serial and cross-sectional dependence, including cross-unit cointegration, without the need to specify the form of dependence or estimate nuisance parameters associated with the dependence. The tests retain high power in small samples, and in contrast to other tests that accommodate cross-sectional dependence, the limiting distributions are valid for panels with finite cross-sectional dimensions.Nonparametric rank tests, unit roots, cointegration, cross-sectional dependence

Integrated Modified OLS Estimation and Fixed-b Inference for Cointegrating Multivariate Polynomial Regressions

This paper shows that the integrated modified OLS (IM-OLS) estimator developed for cointegrating linear regressions in Vogelsang and Wagner (2014a) can be straightforwardly extended to cointegrating multivariate polynomial regressions. These are regression models that include as explanatory variables deterministic variables, integrated processes and products of (non-negative) integer powers of these variables as regressors. The stationary errors are allowed to be serially correlated and the regressors are allowed to be endogenous. The IM-OLS estimator is tuningparameter free and does not require the estimation of any long-run variances. A scalar long-run variance, however, has to be estimated and scaled out when using IM-OLS for inference. In this respect, we consider both standard asymptotic inference as well as fixed-b inference. Fixed-b inference requires that the regression model is of full design. The results may be particularly interesting for specification testing of cointegrating relationships, with RESET-type specification tests following immediately. The simulation section also zooms in on RESET specification testing and illustrates that the performance of IM-OLS is qualitatively comparable to its performance in cointegrating linear regressions

Integrated Modified Least Squares Estimation and (Fixed-b) Inference for Systems of Cointegrating Multivariate Polynomial Regressions

We consider integrated modified least squares estimation for systems of cointegrating multivariate polynomial regressions, i. e., systems of regressions that include deterministic variables, integrated processes and products of these variables as regressors. The errors are allowed to be correlated across equations, over time and with the regressors. Since, under restrictions on the parameters or in case of non-identical regressors across equations, integrated modified OLS and GLS estimation do not, in general, coincide, we discuss in detail restricted integrated generalized least squares estimators and inference based upon them. Furthermore, we develop asymptotically pivotal fixed-b inference, available only in case of full design and for specific hypotheses