Simultaneous factor analysis of dichotomous variables in several groups

A new method is proposed for a simultaneous factor analysis of dichotomous responses from several groups of individuals. The method makes it possible to compare factor loading pattern, factor variances and covariances, and factor means over groups. The method uses information from first and second order proportions and estimates the model by generalized least-squares. Hypotheses regarding different degrees of invariance over groups may be evaluated by a large-sample chi-square test.The research of the first author was supported partly by the Bank of Sweden Tercentenary Foundation under project Structural Equation Models in the Social Sciences, project director Karl G. Jöreskog, and partly by the Swedish Research Council in the Humanistic and Social Sciences under project Analysis of Contingency Tables, project director Bengt Muthén.     

On the Way to a Postmodern Curriculum Theory -- Moving from the Question of Unity to the Question of Difference

This article will examine the consequences of highlighting subject and difference in one of the curriculum theories that has been inspired by postmodernism. The term postmodernism is here first and foremost meant to signify the attempt to combine politics and morality with epistemology in accordance with Levinas, Lyotard and Bauman. The article will highlight some themes that need to be developed further for a postmodernism-inspired curriculum theory. A starting-point is a critique of the type of curriculum theory which has its base in the new sociology of education. From this critique, focused on universal claims, the Habermasian-inspired universalism is quickly and critically dropped and left behind, and another form of reasoning is embarked upon. The latter is inspired by a minotarian politics concept and tries to dissolve universalism as a prerequisite for critical conversations. With this background and with the help of Levinas, the article sets out to talk about difference without reduction to the Same and finally suggest a direction for a postmodern curriculum theory with a normative focus on knowledge.     

Validation of distinct amnesic and executive type memory deficit in a psychiatric sample based on retrieval performance

Studies of localized brain dysfunctions have revealed connections between patterns of cognitive dysfunction and specific profiles of memory impairment. The amnesic type of memory impairment is defined by deficits in both free recall and recognition memory, whereas the dysexecutive memory impairment is characterized by retrieval deficits, i.e. a disproportional impairment in free recall relative to recognition memory. The present study tests whether classifications of psychiatric patients into recall impaired only (= RO group) and Recall and Recognition impaired (= RR group) correspond to the executive type and amnesic type of memory impairment. The alternative hypothesis is that the two groups merely differ in degree of neuropsychological and psychiatric disturbance. Forty-four subjects impaired on California Verbal Learning Test (CVLT) were selected from a larger database of 103 impaired and non-impaired subjects with schizophrenia or recurrent major depression. Subjects were classified into RO and RR groups and compared on measures of memory strategy (recency effect and interference on CVLT), overall neuropsychological function (Stroop Test and WAIS-R similarity) and psychiatric symptom load (positive and negative symptoms). Repeated measures ANOVA showed no effects of group, i.e. the RR group did not perform consistently below the RO group with regard to memory strategy, neuropsychological function or psychiatric symptom load. Two out of three analyses showed group x test interaction, supporting the dissociation of distinct executive and amnesic profiles among psychiatric patients. The RO group was more susceptible to interference but had better recency score than the RR group. The RO had higher negative symptoms while the RR group had higher positive symptoms.     

Modulation of anxiety circuits by serotonergic systems

Anxiety is a complex emotional state associated with sustained heightened autonomic and behavioral arousal and an increase in avoidance behavior. Anxiety-related behavior is a form of risk assessment behavior that is associated with a level of uncertainty or unpredictability regarding the outcome of emotionally salient events, often when both rewarding and aversive outcomes are possible. In this review, we highlight recent advances in our understanding of the neural circuits regulating anxiety states and anxiety-related behavior with an emphasis on the role of brainstem serotonergic systems in modulating anxiety-related circuits. In particular, we explore the possibility that the regulation of anxiety states and anxiety-related behavior by serotonergic systems is dependent on a specific, topographically organized mesolimbocortical serotonergic system that originates in the mid-rostrocaudal and caudal parts of the dorsal raphe nucleus.     

Visual search with biological threat stimuli: accuracy, reaction times, and heart rate changes

Twenty-four participants were given a visual search task of deciding whether all the pictures in 3 x 3 search arrays contained a target picture from a deviant category, and heart rate was measured. The categories were snakes, spiders, flowers, and mushrooms. Shorter reaction times (RTs) were observed for fear-relevant (snake and spider) targets rather than for fear-irrelevant/neutral (flower and mushroom) targets. This difference was most pronounced for the participants presented with a gray-scale version of the search arrays. The 1st interbeat interval (IBI), after the search array onset, showed an effect of the target, whereas the 2nd IBI also showed an effect of the distractors. The results suggest that controlled processing of the task operates together with automatic processing.     

Input and output in distributive theory

Distributive theories evaluate distributions of goods based on candidate recipients’ characteristics, e.g. how well off candidates are, how deserving they are, and whether they fare below sufficiency. But such characteristics vary across possible worlds, so distributive theories may differ in terms of the world which for them settles candidates’ characteristics. This paper examines how distributive theories differ in terms of whether candidate recipients’ relevant characteristics are grounded in the possible world that would take place if the distributor does not intervene (call it the “input” world) or if they are grounded in each possible world that the distributor can bring about through different decisions (call each an “output” world). We illustrate the importance of this distinction in relation to one distributive theory, prioritarianism. As we show, both input and output versions of prioritarianism are plausible interpretations of the literature, and there are good reasons to take input prioritarianism seriously. Ultimately, however, we argue that input prioritarianism should be rejected.     

A short note on the estimation of the asymptotic covariance matrix for polychoric correlations

By using a Taylor expansion of the equations that define the two step estimator for polychoric correlations, the asymptotic covariance matrix for the estimated correlations can be derived in a simple and straightforward way.     

THE NATURALNESS OF CREATION AND REDEMPTIVE INTERESTS IN THEOLOGY,SCIENCE, AND TECHNOLOGY

Abstract. This paper advances ways in which the understandings of “nature” and “creation” can be seen to overlap through specialized relations between humans and their environment. The hope of redemption of nature, united with evidences of grace in the advancements of science, can become helpful guides toward a theological interpretation of technology and the emerging character of human relations with nature.     

Testing the Work Environment Hypothesis of Bullying on a Group Level of Analysis: Psychosocial Factors as Precursors of Observed Workplace Bullying

The present paper scrutinises the work environment hypothesis of bullying by examining relationships between psychosocial factors at work and bullying within departments on a group level of analysis, as compared to the many studies executed on an individual level of analysis. Relationships between quantitative demands, job control, role demands, leadership behaviour and social climate, and observed bullying were studied in a convenience sample consisting of 276 departments with a total of 4,064 respondents. Between‐group bivariate correlations showed relatively strong relationships (r > .52) between the predictors social climate, leadership behaviour, and role demands, respectively, and observed bullying in the department. A two‐factor higher‐level model was formulated for the independent variables yielding two latent factors reflecting an interpersonal domain and a task‐oriented domain, where the former was strongly associated with observed bullying at a group level of analysis (Beta =?.73), while the last factor yielded an insignificant contribution. The results confirm that a poor social work environment exists within departments in which bullying takes place, hence, yielding further support to the work environment hypothesis. In line with the present results, future studies on workplace bullying should include a group level of analysis.     

The effect of exposure duration on visual character identification in single, whole, and partial report

The psychometric function of single-letter identification is typically described as a function of stimulus intensity. However, the effect of stimulus exposure duration on letter identification remains poorly described. This is surprising because the effect of exposure duration has played a central role in modeling performance in whole and partial report (Shibuya & Bundesen, 1988). Therefore, we experimentally investigated visual letter identification as a function of exposure duration. We compared the exponential, the gamma, and the Weibull psychometric functions, all with a temporal offset included, as well as the ex-Gaussian, the log-logistic, and finally the squared-logistic, which is a psychometric function that to our knowledge has not been described before. The log-logistic and the squared-logistic psychometric function fit well to experimental data. Also, we conducted an experiment to test the ability of the psychometric functions to fit single-letter identification data, at different stimulus contrast levels; also here the same psychometric functions prevailed. Finally, after insertion into Bundesen's Theory of Visual Attention (Bundesen, 1990), the same psychometric functions enable closer fits to data from a previous whole and partial report experiment.