Obtaining Diagnostic Classification Model Estimates Using Mplus

Diagnostic classification models (aka cognitive or skills diagnosis models) have shown great promise for evaluating mastery on a multidimensional profile of skills as assessed through examinee responses, but continued development and application of these models has been hindered by a lack of readily available software. In this article we demonstrate how diagnostic classification models may be estimated as confirmatory latent class models using Mplus, thus bridging the gap between the technical presentation of these models and their practical use for assessment in research and applied settings. Using a sample English test of three grammatical skills, we describe how diagnostic classification models can be phrased as latent class models within Mplus and how to obtain the syntax and output needed for estimation and interpretation of the model parameters. We also have written a freely available SAS program that can be used to automatically generate the Mplus syntax. We hope this work will ultimately result in greater access to diagnostic classification models throughout the testing community, from researchers to practitioners.     

Public access to congressional records: Present policy and reform considerations

While the records of the Senate and House of Representatives are among the most valuable sources of information for enhancing public knowledge of congressional operations and decisions, they largely have not been available for examination unless they have been distributed as an official publication. Some have suggested that this situation could be rectified by making Congress subject to the requirements of the Freedom of Information Act. There are, however, both constitutional and practical problems in this approach. Nonetheless, there are those within the two Houses who are aware of the need for reform in this area, and efforts have been made to modify archival policies. Arguably, both citizens and legislators can benefit from improved records access arrangements.     

Identification of important authors in science: A comparison of two methods of identification

This study examines the problem of identification of important authors in science by examining authors in the area of quantum mechanics. An examination was conducted using two methods of identification. The first method was a bibliometric approach and the second a historical approach. A gamma test of association was employed resulting in a finding of significant association between the ranks of authors. The major conclusion was that, when restricted to the same authors, the two methods of identifying important authors produce a statistically significant number of equivalent names. Discussion of the results and areas for further investigation are included.     

The book availability study as an objective measure of performance in a health sciences library

In its search for an objective overall diagnostic evaluation, the University of Illinois Library of the Health Sciences' Program Evaluation Committee selected a book availability measure; it is easy to administer and repeat, results are reproducible, and comparable data exist for other academic and health sciences libraries. The study followed the standard methodology in the literature with minor modifications. Patrons searching for particular books were asked to record item(s) needed and the outcome of the search. Library staff members then determined the reasons for failures in obtaining desired items. The results of the study are five performance scores. The first four represent the percentage probability of a library's operating with ideal effectiveness; the last provides an overall performance score. The scores of the Library of the Health Sciences demonstrated no unusual availability problems. The study was easy to implement and provided meaningful, quantitative, and objective data.     

Bystander Behaviour Among Italian Students

This paper reports the Italian data on the bystanders' project. In the last decade, several studies have been conducted on the prevalence and nature of bullying among primary and secondary students as well as on individual and social risk factors, illustrating that bullying in the Italian context is a widespread phenomenon. No research has been conducted, so far, on the 'bystander' behaviours of those students who see other peers being bullied or bullying others in school either physically, verbally or through sexual coercion (i.e. touching girls). The study was conducted with 594 students (51.9% boys and 48.1% girls), aged 12–16 years old, with a mean age of 13.1 (SD=0.87). They were recruited from six different middle schools, two in each of three different sites in Italy: Northern Italy (Vercelli), Central Italy (Rome) and Southern Italy (Catania). Results showed that though the most likely reaction is supporting the victim by trying to discourage the bully, gender differences emerged, with girls more likely than boys to support the victim and boys more likely to encourage the bully or simply ignore. Differences resembling the same pattern emerged also with regard to own involvement as a bully or a victim. Findings are discussed by looking at possible applications for intervention.