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.     

Measuring and modeling attentional dwell time

Attentional dwell time (AD) defines our inability to perceive spatially separate events when they occur in rapid succession. In the standard AD paradigm, subjects should identify two target stimuli presented briefly at different peripheral locations with a varied stimulus onset asynchrony (SOA). The AD effect is seen as a long-lasting impediment in reporting the second target, culminating at SOAs of 200?C500?ms. Here, we present the first quantitative computational model of the effect??a theory of temporal visual attention. The model is based on the neural theory of visual attention (Bundesen, Habekost, & Kyllingsb?k, Psychological Review, 112, 291?C328 2005) and introduces the novel assumption that a stimulus retained in visual short-term memory takes up visual processing-resources used to encode stimuli into memory. Resources are thus locked and cannot process subsequent stimuli until the stimulus in memory has been recoded, which explains the long-lasting AD effect. The model is used to explain results from two experiments providing detailed individual data from both a standard AD paradigm and an extension with varied exposure duration of the target stimuli. Finally, we discuss new predictions by the model.     

High negative valence does not protect emotional event-related potentials from spatial inattention and perceptual load

Previous research suggests that intense, emotional pictures at fixation elicit an early posterior negativity (EPN) and a late positive potential (LPP) despite manipulations of spatial inattention and perceptual load. However, if high emotional intensity protects against such manipulations, then these manipulations should reduce emotional effects on EPN and LPP more strongly for medium than for intense emotional pictures. To test this prediction, pictures that were high negative, medium negative, or neutral were shown at fixation, and a small letter string was superimposed on the picture center. When participants attended the pictures, there were clear emotional effects on EPN and LPP. When participants attended the letter string, the emotional effects on LPP decreased; this decrease was smaller for medium than for high negative pictures. Thus, opposite of predictions, spatial inattention reduced the emotional effects more strongly for high than for medium negative pictures. As a manipulation of perceptual load, participants performed the letter task with one, three, or six relevant letters. Irrespective of load, EPN and LPP were similar for high and medium negative pictures. Our findings suggest that high negative valence does not protect EPN and LPP more strongly from effects of spatial inattention and perceptual load than does medium negative valence.     

“Imma march’ toward Ka’ba”: Islam in Swedish hip-hop

The common history of Islam and the hip-hop culture can be traced back to the early expression of the culture. Since the early days of hip-hop, Muslims have used hip-hop to convey Islamic messages. Artists driven, in equal parts, by a strong personal belief in Islam and a love for hip-hop music have taken Islamic-themed hip-hop outside its country of birth, the U.S., and have made it into a matter of global concern. In an attempt to contribute to and, hopefully, complicate the picture of what has been called the transglobal hip-hop umma, this article explores how Swedish Muslims articulate their beliefs through hip-hop in Sweden. With examples from both the Swedish mainstream and the underground, it highlights hip-hop music with an Islamic engagement whose aim is to promote and perform what is understood as ??Islamic values,?? such as ethics, peace, social responsibility, and a strong personal belief.     

The Role of Conditional Likelihoods in Latent Variable Modeling

Psychometrika - In psychometrics, the canonical use of conditional likelihoods is for the Rasch model in measurement. Whilst not disputing the utility of conditional likelihoods in measurement, we...