Light Baryon Spectroscopy using the CLAS Spectrometer at Jefferson Laboratory

Baryons are complex systems of confined quarks and gluons and exhibit the characteristic spectra of excited states. The systematics of the baryon excitation spectrum is important to our understanding of the effective degrees of freedom underlying nucleon matter. High-energy electrons and photons are a remarkably clean probe of hadronic matter, providing a microscope for examining the nucleon and the strong nuclear force. Current experimental efforts with the CLAS spectrometer at Jefferson Laboratory utilize highly-polarized frozen-spin targets in combination with polarized photon beams. The status of the recent double-polarization experiments and some preliminary results are discussed in this contribution.Comment: Contribution to the Proceedings of the XIV International Conference on Hadron Spectroscopy, 13-17 June 2011, Munich, German

A Negative Effect of a Contractive Pose is not Evidence for the Positive Effect of an ExpansivePose: Comment on Cuddy, Schultz, and Fosse (2018)

Cuddy,Schultz and Fosse (2018) present the results of p-curve analyses that are interpreted as providing clear evidential value for power posing effects”. This commentary highlights that the vast majority of the studies included in the p-curve analyses were not designed in a way that could speak to the efficacy of power poses relative to a normal or neutral pose. Further, I discuss how the few studies that were designed to shed light on this issue indicate that any overall effect of physical pose on feelings of power, emotions, affect, and self-evaluations is almost entirely due to the negative effect of a contractive pose and not any positive effect of expansive power poses

The Experimental Status of Glueballs

Glueballs and other resonances with large gluonic components are predicted as bound states by Quantum Chromodynamics (QCD). The lightest (scalar) glueball is estimated to have a mass in the range from 1 to 2 GeV/c**2; a pseudoscalar and tensor glueball are expected at higher masses. Many different experiments exploiting a large variety of production mechanisms have presented results in recent years on light mesons with J(PC) = 0(++), 0(-+), and 2(++) quantum numbers. This review looks at the experimental status of glueballs. Good evidence exists for a scalar glueball which is mixed with nearby mesons, but a full understanding is still missing. Evidence for tensor and pseudoscalar glueballs are weak at best. Theoretical expectations of phenomenological models and QCD on the lattice are briefly discussed.Comment: 62 pages, 26 figure

What Shall We Do About Grit? A Critical Review of What We Know and What We Don’t Know

Grit is a construct that is widely studied by educational researchers and that has generally been enthusiastically received by educational practitioners. This essay highlights that many of the core claims about grit have either been unexamined or are directly contradicted by the accumulated empirical evidence. Specifically, there appears to be no reason to accept the combination of perseverance and passion for long-term goals into a single grit construct, nor is there any support for the claim that grit is a particularly good predictor of success and performance in an educational setting or that grit is likely to be responsive to interventions. I describe avenues for future research on grit that may help to clarify if grit can contribute to our understanding of success and performance. These avenues include examinations of possible configural relationships between passion and perseverance, whether grit or grit facets represent necessary but not sufficient conditions for performance, interactions between ability and either grit or the facets of grit in the prediction of performance, possible polynomial relationships between grit or grit facets and performance, and improvements in the manner in which grit is assessed. Alternative predictors of performance that are more strongly related to success and performance and that may be more responsive to interventions are also discussed

Questionable Research Practices when Using Confirmatory Factor Analysis

Purpose The purpose of this paper is to describe common questionable research practices (QRPs) engaged in by management researchers who use confirmatory factor analysis (CFA) as part of their analysis. Design/methodology/approach The authors describe seven questionable analytic practices and then review one year of journal articles published in three top-tier management journals to estimate the base rate of these practices. Findings The authors find that CFA analyses are characterized by a high base rate of QRPs with one practice occurring for over 90 percent of all assessed articles. Research limitations/implications The findings of this paper call into question the validity and trustworthiness of results reported in much of the management literature. Practical implications The authors provide tentative guidelines of how editors and reviewers might reduce the degree to which the management literature is characterized by these QRPs. Originality/value This is the first paper to estimate the base rate of six QRPs relating to the widely used analytic tool referred to as CFA in the management literature

The generalizability of transformational leadership across cultures: a meta-analysis

Purpose The purpose of this paper is to investigate whether the effectiveness of transformational leadership behaviors are moderated by a country’s cultural values and cultural practices. Design/methodology/approach The authors describe a meta-analytic review of the relationship between transformational leadership and employee performance (task performance and OCBs) using data from over 57,000 individuals, 215 samples and 34 countries. The authors examine whether this relationship is moderated by the cultural values and practices of the country in which the study was located – after first controlling for methodological factors. Findings The authors find that cultural values and practices moderate the transformational leadership – employee performance relationship such that the relationship is much stronger in countries whose culture is incongruent with transformational leadership. Research limitations/implications Data were only available for 34 countries and it is unclear what role industry type and job type play in determining transformational leadership effectiveness or if these situational variables are confounded with culture. The findings call into question the generalizability of transformational leadership across countries and cultures. Practical implications The findings suggest that the value of transformational leadership behaviors may be limited in developed economies such as Western Europe and North America, while transformational leadership is most effective in Africa, the Middle East, South America and parts of Southeast Asia. Originality/value This is the first paper to examine the generalizability of transformational leadership across 34 countries and is by far the largest review ever conducted into the relationship between transformational leadership and subordinate performance

Questionable association between front boarding and air rage

DeCelles and Norton (1) conclude that physical inequality (the presence of a first-class cabin) on airplanes is associated with a greater number of air rage incidents in economy class, and that situational inequality (boarding from the front rather than the middle of the airplane) is associated with a greater number of air rage incidents in both economy class and first class. Their study has many flaws that invalidate their conclusions, but we focus on just one, their failure to recognize a statistical artifact in their analyses

Methods for Evaluating Educational Programs – Does Writing Center Participation Affect Student Achievement?

This paper evaluates the eff ectiveness of the introduction of a Writing Center at a university. The center has the purpose to provide subject-specifi c courses that aim to improve students‘ abilities of scientifi c writing. In order to deal with presumed selfperceptional biases of students in feedback surveys, we use diff erent quantitative evaluation methods and compare the results to corresponding qualitative student surveys. Based on this evaluation, we present and discuss the validity of the approaches to evaluate educational programs. Although almost all students reported the writing courses to be helpful, we fi nd no signifi cant eff ect of course participation on students‘ grades. We attribute the diff erence in the results between quantitative methods and qualitative surveys to the inappropriateness of student course evaluations for assessing the eff ectiveness of educational measures.Performance evaluation; educational programs; student evaluation; empirical methods

Research on failure of equipment when subject to vibration

This report is in the nature of a progress report; it sets forth in some detail the status of the research on the several tasks as of the date of the report. In general, the research was incomplete on that date and no conclusions are presented. The report is written primarily to keep parsonnel of the sponsoring agency apprised of work that has been accomplished. It is not intended for outside distribution or publication. This is the first annual report under a continuing research project whose objective is to gain a better understanding of the failure of equipment when subjected to vibration. This is essential to (1) the attainment of improved practices in design of equipment that is required to withstand vibration and (Z) to the application of more rational procedures for conducting vibration tests in the laboratory. In principle, the laboratory test creates a vibration condition that causes such failure of the equipment as would occur during actual service use. However, a laboratory test cannot reproduce the service condition in all of its details; thus, a good knowledge of the mechanics of failure is necessary to relate laboratory and service conditions in a constructive manner. The research program includes two general aspects that are being pursued concurrently, at least in the initial phase of the research program: 1. Actual electronic and mechanical components of equipment with known susceptibility to failure; e.g., a vacuum tube in the initial task, are subjected to vibration of various defined types. The components are connected in circuits designed to simulate a typical application and the effect of vibration on the operation of the circuits is monitored. An objective of the experiment is to infer from the circuit operation and response of the component an analog that may be used to describe the characteristics of the component that are significant with respect to vibration. Such analogs are then used in further analyses of the component. 2. Concurrent with the above experiments using actual components, a group of analogs having apparent application to known components is selected initially. Additional analogs are added to this group as experimental evaluation of actual components proceeds. The response of each selected analog to various idealized forms of vibration is investigated. Then from the relation between the response of the analog to such vibration and observed performance of the component to which the analog is related. the response of the component and its operational capability under more general types of vibration can be predicted. A representative vacuum tube has been mounted upon a vibration exciter and subjected to both sinusoidal and random vibration. Its performance was Monitored by noting the voltage output (microphonic noise) that could be ascribed to vibration. This report includes records of output voltage as a function of vibration frequency, for further use in attempting to infer an appropriate mechanical analog. Five idealized forms of excitation have been selected for initial investigation: (1) sinusoid, (2) combined sinusoids, (3) scanning or sweeping sinusoid, (4) broad band random with Gaussian distribution and (5) broad band random with magnitude limitation. For each type of excitation, the response of the most common mechanical analog, a damped, single degree of freedom system, has been analyzed. By relating the characteristics of the analog to an actual component and applying appropriate criteria of failure, these responses are of use in predicting the performance capability of the component. For example, consider a structure vulnerable to failure by fatigue; then the distribution of response cycles included in the analysis of the analog response when taken with hypotheses of cumulative damage is applicable to predict the fatigue life. Some experiments on fatigue have been carried out, with the objective of determining whether existing hypotheses of cumulative damage are applicable to the problem being discussed here. A simplified structure having certain characteristics of a typical equipment has been subjected to fatigue tests. Because of certain unanticipated characteristics of the response of the structure, it has become evident that additional experiments are required to interpret the results obtained to date. This phase of the program is continuing. Section 1 of the report includes a detailed discussion of research program, its hypotheses and objectives. A brief summary of the results also is included in Section 1, with references to other sections of the report and to the appendices when complete details are set forth