Vector Autoregressions, Policy Analysis, and Directed Acyclic Graphs: An Application to the U.S. Economy

The paper considers the use of directed acyclic graphs (DAGs), and their construction from observational data with PC-algorithm TETRAD II, in providing over-identifying restrictions on the innovations from a vector autoregression. Results from Sims’ 1986 model of the US economy are replicated and compared using these data-driven techniques. The directed graph results show Sims’ six-variable VAR is not rich enough to provide an unambiguous ordering at usual levels of statistical significance. A significance level in the neighborhood of 30 % is required to find a clear structural ordering. Although the DAG results are in agreement with Sims’ theory-based model for unemployment, differences are noted for the other five variables: income, money supply, price level, interest rates, and investment. Overall the DAG results are broadly consistent with a monetarist view with adaptive expectations and no hyperinflation.vector autoregression; directed graphs; policy analysis

The crystal and molecular structure of Hydridotetrakis(diethyl phenylphosphonite)cobalt(I)

An X-ray structure determination of the title compound shows that the co-ordination about the cobalt atom is approximately trigonal bipyramidal; n.m.r. data indicate that the complex is non-rigid in solution

Featured Piece

This year the General Editors decided to create a feature piece to show our appreciation for the History Department. We selected four professors from the faculty to answer a question about history: what figure/event/idea inspires your interest in history? Reading their responses helped give us insight into the thoughts of these brilliant minds and further help us understand their passion for the subject we all share a common love and interest in. We hope that you enjoy reading their responses as much as we did. The four members of the faculty we spoke with are Dr. Timothy Shannon, Dr. Ian Isherwood, Dr. Jill Titus, and Dr. Scott Hancock

`Unhinging' the surfaces of higher-order topological insulators and superconductors

We show that the chiral Dirac and Majorana hinge modes in three-dimensional higher-order topological insulators (HOTIs) and superconductors (HOTSCs) can be gapped while preserving the protecting $\mathsf{C}_{2n}\mathcal T$ symmetry upon the introduction of non-Abelian surface topological order. In both cases, the topological order on a single side surface breaks time reversal symmetry, but appears with its time-reversal conjugate on alternating sides in a $\mathsf{C}_{2n}\mathcal T$ preserving pattern. In the absence of the HOTI/HOTSC bulk, such a pattern necessarily involves gapless chiral modes on hinges between $\mathsf{C}_{2n}\mathcal T$-conjugate domains. However, using a combination of $K$-matrix and anyon condensation arguments, we show that on the boundary of a 3D HOTI/HOTSC these topological orders are fully gapped and hence `anomalous'. Our results suggest that new patterns of surface and hinge states can be engineered by selectively introducing topological order only on specific surfaces

Curriculum Development Project in Health Education for Lyle School District No. 406; Scope and Sequence for Kindergarten through Twelfth Grade and Curriculum Guide for Ninth Grade Health

Small school districts rarely have curriculum direction, let alone curriculum guides. This writer has often overheard staff members exclaim, It would help so much if I knew what I am supposed to teach, or It would be nice if there was some planned progression that students were exposed to. Small school districts usually cannot afford the luxury of specialized curriculum staff working on curriculum projects. This writer, along with two other staff members was fortunate to attend a health education workshop sponsored by ESD No. 112 in the fall of 1974. A process of curriculum development for health education was one of the items explained at the workshop. The process, with modifications, could provide a small school district the means by which curriculum development becomes a continuing reality. As a result of the completion of this project, this writer will have led staff members through a process by which they will have become better acquainted with their respective responsibilities in teaching health education

An examination of the associations between the locations of probationers and crimes: A city block-level analysis

This research will use adult probation data from the Douglas County Court Probation Office for 2000 and 2001 to evaluate the relationship between the locations of probationers and their possible effects on the amount of crime on residential city blocks in Omaha, Nebraska. The analyses will relate the probation data to the dependent variables that are based on the Part I Index Crimes obtained from the Omaha Police Department. The research will attempt to evaluate the effects of probationers on the amount of crime on city blocks and compare this with the effects of block-level characteristics and crime on the locations of probationers. This comparison involves using strategies related to Granger Causality to assess whether the presence of probationers leads to crime rather than high crime areas becoming areas where probationers live. Matrix Exponential Spatial Specification (MESS) regression will also be used to evaluate these effects because this technique permits adjusting for spatial autocorrelation which could be important when dealing with very small unit of analysis such as city blocks

Barriers To The Use Of Information And Communication Technologies In Teaching And Learning Business Education

Education is an instrument “per excellence” for national development. Business education is one of the programs run in about 117 universities in Nigeria. It was believed that business education has the capacity to bring about the required development since it is a course of instruction aimed at inculcating in the youth the skills, attitudes and competencies which are necessary to empower them to be gainfully engaged so that they will be useful citizens and contribute to the development of Nigeria and the society. However, there seemed to be gaps between the nation’s educational objectives and their realization. The obvious indicators to this fact are poor skills of graduates who cannot fit into the office of today, unemployment, poverty and underdevelopment of the country. Information and Communication Technologies (ICTs) where properly utilized is capable of making the difference in empowering the students with the needed skills, attitudes and competencies. This study explored the barriers to the use of ICTs in teaching and learning business education. The researcher constructed 15 questionnaire items from research reports relevant to the study. The questionnaire was validated using Cronbach Alpha which yielded a reliability coefficient of 0.78. A total of 256 questionnaire items were administered to 202 business educators and 54 students of business education respectively from Universities offering business education in Nigeria and all of which were completed and retrieved. The Research Question “what are the barriers to the use of ICTs in teaching and learning business education in Nigeria?” was answered using mean rating and standard deviation. The Hypothesis of no significant difference in the mean responses of business educators and business education students from universities regarding barriers to the use of ICTs in teaching and learning business education was tested using student T-test. The study revealed that all the constructs, except one, constituted barriers to the use of ICTs in teaching and learning business education in Nigeria universities. it was concluded that the revealed barriers be tackled by the government, the university authorities, the teachers and the students so that the university environment would be repositioned to play its role of empowering the youth with the skills, attitude and competencies needed for Nigeria’s development

An Examination of the Associations Between the Locations of Probationers and Crimes: A City Block-Level Analysis

This research will use adult probation data from the Douglas County Court Probation Office for 2000 and 2001 to evaluate the relationship between the locations of probationers and their possible effects on the amount of crime on residential city blocks in Omaha, Nebraska. The analyses will relate the probation data to the dependent variables that are based on the Part I Index Crimes obtained from the Omaha Police Department. The research will attempt to evaluate the effects of probationers on the amount of crime on city blocks and compare this with the effects of block-level characteristics and crime on the locations of probationers. This comparison involves using strategies related to Granger Causality to assess whether the presence of probationers leads to crime rather than high crime areas becoming areas where probationers live. Matrix Exponential Spatial Specification (MESS) regression will also be used to evaluate these effects because this technique permits adjusting for spatial autocorrelation which could be important when dealing with very small unit of analysis such as city blocks