Extending exploratory diagnostic classification models: Inferring the effect of covariates

Diagnostic models provide a statistical framework for designing formative assessments by classifying student knowledge profiles according to a collection of fine-grained attributes. The context and ecosystem in which students learn may play an important role in skill mastery, and it is therefore important to develop methods for incorporating student covariates into diagnostic models. Including covariates may provide researchers and practitioners with the ability to evaluate novel interventions or understand the role of background knowledge in attribute mastery. Existing research is designed to include covariates in confirmatory diagnostic models, which are also known as restricted latent class models. We propose new methods for including covariates in exploratory RLCMs that jointly infer the latent structure and evaluate the role of covariates on performance and skill mastery. We present a novel Bayesian formulation and report a Markov chain Monte Carlo algorithm using a Metropolis-within-Gibbs algorithm for approximating the model parameter posterior distribution. We report Monte Carlo simulation evidence regarding the accuracy of our new methods and present results from an application that examines the role of student background knowledge on the mastery of a probability data set.     

Factorial validity and measurement invariance of the Revised Physical Self-Perception Profile (PSPP-R) in three countries

The revised physical self-perception profile (PSPP-R) was constructed to measure both perceived competence and importance linked to domains of the physical self. In the present study, we tested the factorial validity of the PSPP-R, using confirmatory factor analytic approach, on samples of university students from three different countries: Sweden, Turkey, and the UK. Multi-sample covariance structure analyses were also used to test the invariance of the PSPP-R across the three national samples. First-order four-factor models, including the latent factors of sport competence, physical conditioning, body attractiveness and physical strength, demonstrated good-fit with the data both for competence and importance factors. Second-order factor models, incorporating the second-order latent domain factor of physical self-worth also exhibited good-fit with the data. Factor patterns and covariances were invariant across samples for both competence and importance scales. Item intercepts were also invariant for the importance scales, whereas partial invariance of intercepts was supported for competence scales. The results are discussed with reference to the validity of the original physical self-perception profile and cross-cultural studies on the physical self.     

Structural,elastic, electronic,phonon and thermal properties of Ir3Ta and Rh3Ta alloys

We have studied the structural, elastic, electronic, phonon and thermodynamic properties of Ir₃Ta and Rh₃Ta alloys, using ab initio calculations. For the L1₂ phase, we report the calculated lattice constants, bulk modulus and elastic constants, and these values are compared with previously published values. We also derive the elastic constants from the values of the slopes of the acoustic branches in the phonon dispersion curves. The band structures show that both materials are metallic. The phonon dispersion curves, and their corresponding total and projected densities of states, are obtained using a linear response in the framework of the density functional perturbation theory. The specific heat capacity at constant volume and different temperatures is calculated, and this aspect is discussed using the quasi-harmonic approximation.     

Cross-cultural invariance of the basic psychological needs in exercise scale and need satisfaction latent mean differences among Greek,Spanish, Portuguese and Turkish samples

ObjectivesThe present study examined the extent to which scores from the Basic Psychological Needs in Exercise Scale are measurement invariant across Greek, Spanish, Portuguese, and Turkish samples of exercise participants.DesignA cross-sectional design wherein responses were analyzed from 504 Greek participants, 518 Spanish participants, 989 Portuguese participants, and 686 Turkish participants.MethodsData on exercise participants' need satisfaction were collected using the Basic Psychological Needs in Exercise Scale (Vlachopoulos & Michailidou, 2006) after back translation for the languages involved in the study.ResultsMulti-sample confirmatory factor analyses showed that BPNES scores were largely invariant at the configural, metric, and strong invariance levels, but not at the strict invariance level for Spanish, Portuguese, and Turkish samples compared to the Greek sample. Portuguese participants reported higher levels of satisfaction for all three needs compared to Greek participants, while for Spanish participants this was the case only for competence and relatedness. Turkish participants did not differ from Greek participants.ConclusionsThe present findings support valid cross-cultural comparisons at the latent variance/covariance level and the latent/observed mean level of the constructs of autonomy, competence, and relatedness using the BPNES.     

Hospitalization of Children with Cystic Fibrosis Adversely Affects Mothers’ Physical Activity,Sleep Quality,and Psychological Status

Having a child with a chronic disease can cause anxiety and depression, which may impair the sleep quality of mothers. The aim of this study was to compare physical activity level, sleep quality, anxiety and depression in mothers of hospitalized cystic fibrosis patients, cystic fibrosis outpatients and healthy controls. Twenty-three of the patients were hospitalized and 38 were outpatients and 37 age-matched healthy children served as controls. The mothers’ fatigue levels, sleep disturbances, stress levels and perceptions of their child’s disease severity were assessed with a Visual Analog Scale. The International Physical Activity Questionnaire, Pittsburgh Sleep Quality Index and Hospital Anxiety and Depression Scale were administered to the mothers of children. Mothers of hospitalized and outpatient cystic fibrosis children had significantly higher fatigue severity, sleep disturbance, and stress level according to Visual Analog Scale than mothers of healthy controls. All of International Physical Activity Questionnaire scores were significantly lower in cystic fibrosis patients’ mothers than healthy controls’. Hospital Anxiety and Depression Scale depression score, Pittsburgh Sleep Quality Index subdomains and total scores of hospitalized patients’ mothers were higher than those of the other two groups (p?<?0.05). Chronic illness in children with cystic fibrosis may impair the physical activity level, sleep quality and psychological state of their mothers, especially during hospitalization period.     

Authoritarian Predispositions and Attitudes Towards Redistribution

Authoritarian predispositions are associated with a preference for order, certainty, and security. Using data from European Social Surveys (ESS), we show that this association extends to attitudes towards redistributive policies. We demonstrate that support for redistributive policies that emphasize the government’s responsibility to provide old age, health, and unemployment benefits are positively associated with authoritarian predispositions. We also provide evidence that perceived economic threats moderate this relationship such that, for individuals who perceive higher levels of economic threat, the relationship between authoritarian predispositions and support for government responsibility is stronger. These results show that authoritarian predispositions are not only associated with social preferences but also attitudes towards economic policies.     

Religion and Democratic Commitment: A Unifying Motivational Framework

There is no easy answer to the question of whether religiosity promotes or hinders commitment to democracy. Earlier research largely pointed to religiosity as a source of antidemocratic orientations. More recent empirical evidence is less conclusive, however, suggesting that the effect of religiosity on democratic commitment could be positive, negative, or null. We review the existing approaches to the study of religiosity and democratic commitment, focusing on support for the democratic system, political engagement, and political tolerance, by distinguishing accounts that examine a single dimension of religiosity from accounts that adopt a multidimensional approach. We show that multidimensional approaches, while effective in accounting for the effect of religiosity on discrete democratic norms, fall short of accounting for some of the inconsistencies in the literature and in identifying the mechanisms that may be responsible for shaping how religiosity affects endorsement of democratic norms as a whole. To fill this gap, we propose the Religious Motivations and Expressions (REME) model. Applying theories of goal constructs to religion, this model maps associations between three religious expressions (belief, social behavior, and private behavior) and the religious motivations that underly these expressions. We discuss how inconsistent associations between religiosity and elements of democratic commitment can be rendered interpretable once the motivations underlying religious expressions, as well as contextual information, are accounted for. We contend that applying goal constructs to religion is critical for understanding the nature of the religion-democracy nexus.     

The associations between adult attachment,posttraumatic symptoms,and posttraumatic growth

Background and Objectives: Individual differences after trauma vary considerably and can range from posttraumatic stress disorder (PTSD) to posttraumatic growth (PTG). Current theoretical models cannot fully explain this variability. Therefore, we integrated attachment theory with Ehlers and Clark's model of PTSD to understand whether attachment style is associated with negative appraisals of a traumatic event(s), posttraumatic stress symptoms (PTS), and PTG. Our aim was to test this integrated model PTSD in an analog sample who had experienced at least one traumatic event. Design: We used structural equation modeling to test the association of adult attachment and posttraumatic cognitions (self and world/others) with PTS and PTG using a cross-sectional, correlational design. Methods: The sample comprised 393 university staff and students (Range_Age= 18–49, 85% females) who completed online measures. Results: Attachment anxiety and negative posttraumatic self-cognitions were positively associated. Negative posttraumatic self-cognitions were positively associated with PTS. Attachment anxiety had an indirect effect (via negative posttraumatic self-cognitions) on PTS, whereas attachment avoidance predicted more negative posttraumatic world cognitions and lower perceived PTG. Conclusions: The study highlights the importance of considering how attachment styles influence posttraumatic emotion regulation and cognitive processing of the trauma to determine posttraumatic mental health.