Reliability of Pass and Fail Decisions on Tests Employing Cut Scores

The study evaluated the reliability of pass and fail classifications for several teacher certification tests. Since these tests are used in the context of a cut score to classify examinees as pass and fail, evaluating the accuracy and consistency of these classifications is important. The classification accuracy and consistency statistics were estimated using the RELCLASS software. Results indicated the following. (1) The 29 teacher certification tests that were examined had a relatively high classification accuracy (0.827 to 0.999) and consistency (0.760 to 0.999). (2) Both classification accuracy and consistency increased as the difference between the mean and cut score increased. (3) Classification accuracy and consistency was higher for multiple-choice (MC) as compared to tests consisting of only constructed-response (CR) items or a combination of CR and MC items.     

Eugenol as an anti-stress agent: modulation of hypothalamic-pituitary-adrenal axis and brain monoaminergic systems in a rat model of stress

Stress is the leading psychopathological cause for several mental disorders. Physiological and psychological responses to stress are mediated by the hypothalamic?pituitary?adrenal (HPA), sympathoadrenal system (SAS), and brain monoaminergic systems (BMS). Eugenol is reported to substantially modulate brain functions by regulating voltage-gated cation channels and release of neurotransmitters. This study was designed to evaluate the anti-stress effect of eugenol in the 4-h restraint model using rats. Ulcer index was measured as a parameter of the stress response. HPA axis and the SAS were monitored by estimating plasma corticosterone and norepinephrine (NE), respectively. Analysis of NE, serotonin (5-HT), dopamine, and their metabolites in discrete brain regions was performed to understand the role of BMS in the anti-stress effect of eugenol. Stress exposure increased the ulcer index as well as plasma corticosterone and NE levels. Eugenol pretreatment for 7 days decreased the stress-induced increase in ulcer index and plasma corticosterone but not NE levels, indicating a preferential effect on the HPA axis. Furthermore, eugenol showed a ?U?-shaped dose?response curve in decreasing ulcer index and plasma corticosterone levels. Eugenol also reversed the stress-induced changes in 5-HT levels in all brain regions, whereas NE levels were reversed in all brain regions except hippocampus. These results suggest that eugenol possesses significant anti-stress activity in the 4-h restraint model and the effect is due to modulation of HPA and BMS.     

A new allotropic structure of silver nanocrystals nucleated and grown over planar polymer molecules

Polymer molecules of polyvinyl alcohol (PVA) serve as a good Ag⁺?→?Ag⁰ reducer as well as a template to produce Ag⁰ nanocrystals of anisotropic shapes. Thin Ag–PVA films (50–100?µm thick) were prepared by carrying out the reaction in aqueous PVA (under heating conditions) and then spin casting the sample in this shape. A topotactic Ag⁺?→?Ag⁰ reaction and in-situ Ag⁰ growth occur in support over the PVA molecules (as per the local structure and Ag⁰–PVA interactions) of elongated surfaces. The Ag⁰ state is confirmed with 3d _5/2 and 3d _3/2 XPS signals of 368.37 and 374.13?eV binding energies, respectively. As analyzed with X-ray diffraction, it is a new allotrope with an orthorhombic structure, lattice parameters a?=?0.8535, b?=?0.8410?nm and c?=?0.4119?nm, and density ρ?=?9.69?g?cm^?3. On heating in air, the well-known cubic structure develops, a?=?0.4082?nm (ρ?=?10.53?g?cm^?3) after 150°C, whereas a?=?0.4071?nm (ρ?= 10.61?g?cm^?3) after 300°C for 2?h. According to proposed models, it is a vacancy-stabilized allotrope, which evolves from multiply twinned particles.     

Organizational identification and organizational commitment: Distinct aspects of two related concepts

The conceptual differences between organizational commitment and identification are discussed theoretically and examined empirically. The present study is based on data of 450 employees of five different organizations in Nepal. A revised eight-item scale was designed out of Cheney's Organizational Identification Questionnaire to assess the core aspects of organizational identification. In confirmatory factor analyses, identification was found to be distinguishable from four related commitment concepts (i.e. affective, continuance, normative, and attitudinal commitment).     

Reporting subscores for institutions

Recently, there has been an increasing level of interest in reporting subscores for components of larger assessments. This paper examines the issue of reporting subscores at an aggregate level, especially at the level of institutions to which the examinees belong. A new statistical approach based on classical test theory is proposed to assess when subscores at the institutional level have any added value over the total scores. The methods are applied to two operational data sets. For the data under study, the observed results provide little support in favour of reporting subscores for either examinees or institutions.     

Success and failure of new speech category learning in adulthood: Consequences of learned Hebbian attractors in topographic maps

The influence of a native language on learning new speech sounds in adulthood is addressed using a network model in which speech categories are attractors implemented through interactive activation and Hebbian learning. The network has a representation layer that receives topographic projections from an input layer and has reciprocal excitatory connections with deeper layers. When applied to an experiment in which Japanese adults were trained to distinguish the English /r/-/l/ contrast (McCandliss, Fiez, Protopapas, Conway, & McClelland, 2002), the model can account for many aspects of the experimental results, such as the time course and outcome of the learning, how it varies as a function of feedback, the relative efficacy of adaptive and initially easy training stimuli versus nonadaptive and difficult stimuli, and the development of a discrimination peak at the acquired category boundary. The model is also able to capture some aspects of the individual differences in learning. nt]mis|This research was supported by NIMH Grant MH64445 and Training Grant 5T32-MH019983-07. The authors thank Susan G. Guion for generously providing the recordings from her experiment and Mary L. Conway for her assistance with data analysis. Correspondence concerning this article should be addressed to J. L. McClelland, Department of Psychology, 450 Serra Mall, Jordan Hall, Bldg. 420, Stanford, CA 94305     

Organizational Commitment in Nepalese Settings

This study examines the three-dimensional organizational commitment (OC) concept (Meyer & Allen, 1997) in Nepal. Standardized questionnaires were administered to a heterogeneous sample of 103 employees of four different Nepalese organizations (bank, food corporation, telecommunication, and an airline). Exploratory factor and confirmatory factor analyses replicate the dimensionality of OC, i.e., the three facets of commitment (affective, normative, and continuance commitment) could be found also in a developing country with a cultural background very different from the places where the commitment concept was originally formulated. Antecedents and consequences of organizational commitment were investigated by multiple regression analyses. Continuance and normative commitment were both explained by job characteristics, i.e., by the perception of the job as interesting, affective commitment could not be explained with the set of variables used in this study. However, it is affective commitment which particularly accounts for variance in search intentions as well as in turnover intentions.     

Organizational citizenship behavior and organizational commitment in Nepal

The present study examines the structure of organizational citizenship behavior (OCB) and its relation to organizational commitment in Nepal. Four-hundred and fifty employees of five Nepalese organizations filled out standardized questionnaires. Exploratory and confirmatory factor analyses revealed two factors of OCB, altruism and compliance, replicating Western models of extra-role behavior. Structural equation analysis showed a positive relation between affective and normative commitment on the one hand and both citizenship factors on the other. Continuance commitment was negatively related to compliance and unrelated to altruism. The findings thus confirmed the structure and usefulness of the concepts in an under-researched geographical area. Findings of the research are discussed within the Nepalese sociocultural context.     

Elderly homicide in Chicago: a research note

There is a body of knowledge about elderly crime victims, but we know little about the characteristics of elderly perpetrators, especially of homicide. The few studies that have been published are based on small samples and are somewhat dated. In an examination of homicides committed in Chicago over a 31-year period, we compared cases involving perpetrators aged over 60 years (n = 443) with those involving younger perpetrators (n = 24,066). There were a number of significant differences. Elderly killers were more likely to be White and to commit suicide afterwards. Their victims were more likely to be spouses, females, and aged over 60 years. Inter-racial homicide was more common for younger offenders. The low number of homicides involving the elderly is explained by reference to routine activity theory.     

Reporting Diagnostic Scores in Educational Testing: Temptations,Pitfalls, and Some Solutions

Diagnostic scores are of increasing interest in educational testing due to their potential remedial and instructional benefit. Naturally, the number of educational tests that report diagnostic scores is on the rise, as are the number of research publications on such scores. This article provides a critical evaluation of diagnostic score reporting in educational testing. The existing methods for diagnostic score reporting are discussed. A recent method (Haberman, 2008a Haberman, S. J. 2008a. When can subscores have value?. Journal of Educational and Behavioral Statistics, 33: 204–229. [Crossref], [Web of Science ®] , [Google Scholar]) that examines if diagnostic scores are worth reporting is reviewed. It is demonstrated, using results from operational and simulated data, that diagnostic scores have to be based on a sufficient number of items and have to be sufficiently distinct from each other to be worth reporting and that several operationally reported subscores are actually not worth reporting. Several recommendations are made for those interested to report diagnostic scores for educational tests.