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Background: A potential problem of low-stakes large-scale assessments such as the Programme for the International Assessment of Adult Competencies (PIAAC) is low test-taking engagement. The present study pursued two goals in order to better understand conditioning factors of test-taking disengagement: First, a model-based approach was used to investigate whether item indicators of disengagement constitute a continuous latent person variable by domain. Second, the effects of person and item characteristics were jointly tested using explanatory item response models. Methods: Analyses were based on the Canadian sample of Round 1 of the PIAAC, with N = 26,683 participants completing test items in the domains of literacy, numeracy, and problem solving. Binary item disengagement indicators were created by means of item response time thresholds. Results: The results showed that disengagement indicators define a latent dimension by domain. Disengagement increased with lower educational attainment, lower cognitive skills, and when the test language was not the participant's native language. Gender did not exert any effect on disengagement, while age had a positive effect for problem solving only. An item's location in the second of two assessment modules was positively related to disengagement, as was item difficulty. The latter effect was negatively moderated by cognitive skill, suggesting that poor test-takers are especially likely to disengage with more difficult items. Conclusions: The negative effect of cognitive skill, the positive effect of item difficulty, and their negative interaction effect support the assumption that disengagement is the outcome of individual expectations about success (informed disengagement).

When citizens hold multiple values relevant to their policy opinions, they might experience value conflict, value reconciliation or make a value trade-off. Yet, it is unclear which individuals are able to manage their multiple values in these ways. We posit a sophistication-interaction theory of value pluralism where the most politically sophisticated individuals are able to reconcile the existence of multiple values, thus increasing the stability of their policy opinions. We test this hypothesis using a series of heteroskedastic graded item response theory models of public opinion toward policies related to climate change. We find that people structure their policy preferences toward climate change policies in values toward the environment and the economy, but only the most sophisticated citizens are able to reconcile the potential conflict between these values.

We use spectra from CARMENES, the Calar Alto high-Resolution search for M dwarfs with Exo-earths with Near-infrared and optical Echelle Spectrographs, to search for periods in chromospheric indices in 16 M0-M2 dwarfs. We measure spectral indices in the Hα, the Ca II infrared triplet (IRT), and the Na I D lines to study which of these indices are best-suited to finding rotation periods in these stars. Moreover, we test a number of different period-search algorithms, namely the string length method, the phase dispersion minimisation, the generalized Lomb-Scargle periodogram, and the Gaussian process regression with quasi-periodic kernel. We find periods in four stars using Hα and in five stars using the Ca II IRT, two of which have not been found before. Our results show that both Hα and the Ca II IRT lines are well suited for period searches, with the Ca II IRT index performing slightly better than Hα. Unfortunately, the Na I D lines are strongly affected by telluric airglow, and we could not find any rotation period using this index. Further, different definitions of the line indices have no major impact on the results. Comparing the different search methods, the string length method and the phase dispersion minimisation perform worst, while Gaussian process models produce the smallest numbers of false positives and non-detections.© 2019 ESO. ; B.F. acknowledges funding by the DFG under Cz 222/1-1. CARMENES is an instrument for the Centro Astronomico Hispano-Aleman de Calar Alto (CAHA, Almeria, Spain). CARMENES is funded by the German Max-Planck-Gesellschaft (MPG), the Spanish Consejo Superior de Investigaciones Cientificas (CSIC), the European Union through FEDER/ERF FICTS-2011-02 funds, and the members of the CARMENES Consortium (Max-Planck-Institut fur Astronomie, Instituto de Astrofisica de Andalucia, Landessternwarte Konigstuhl, Institut de Ciencies de l'Espai, Institut fur Astrophysik Gottingen, Universidad Complutense de Madrid, Thuringer Landessternwarte Tautenburg, Instituto de Astrofisica de Canarias, Hamburger Sternwarte, Centro de Astrobiologia and Centro Astronomico Hispano-Aleman), with additional contributions by the Spanish Ministry of Economy, the German Science Foundation through the Major Research Instrumentation Programme and DFG Research Unit FOR2544 >Blue Planets around Red Stars>, the Klaus Tschira Stiftung, the states of Baden-Wurttemberg and Niedersachsen, and by the Junta de Andalucia. ; Peer Reviewed

Replication Code for: van der Meer and Ouattara, (date), "Putting 'political' back in political trust: an IRT test of the unidimensionality and cross-national equivalence of political trust measures" Quality and Quantity. Forthcoming. https://link.springer.com/journal/11135 . Abstract: Much research intro political trust—its causes, correlates and trends—builds on the twin assumptions that trust in a wide range of political institutions is ultimately an expression of (1) a singular and (2) a crossnationally equivalent underlying attitude. Yet, the widespread assumptions of unidimensionality and crossnational equivalence of political trust is at odds with the dominant conceptual understanding of political trust as a relational concept, driven by subjects, objects, and their interplay. This paper employs Rasch modelling as a direct, strict test of unidimensionality, equivalence and item hierarchy. We test the fit of the Rasch model on political trust items in seven widely used, cross-national surveys (World Values Survey, Afrobarometer, Arabbarometer, Asian Barometer, Eurobarometer, European Social Survey, and Latinobarometro), covering 161 national surveys in 119 countries across the globe. We find that the unidimensional specification of the Rasch model does not fit the standard political trust question batteries. Political trust is not cross nationally equivalent; trust in specific political institutions is more than a mere indicator of an underlying attitude. This conclusion does not impede cross-national research into political trust; rather it illustrates the need for consistent robustness checks across a range of objects of political trust. Our findings open up new venues for substantive research questions on specific objects of political trust and their relationships.

Using an Item response theory (IRT) analysis, this study examined ethnic and gender groups differences in exposure to content material (i.e. access to curriculum) assessed on the 12th grade NAEP US History 2010 exam. Employing multi-step data analysis procedures, authors examined race and gender using the NAEP Item Mapping Tool available through NCES. Results revealed item-level patterns, which suggest that females and Black students are more likely to answer questions, related to social history, particularly the Civil Rights, when accounting for student achievement. While instructional exposure matters, how students of similar performance differentiate themselves on item response is related to demographics. These findings have substantial implications for social studies, which include the need to develop a more democratic curriculum that reflects the cultural identities of students in order to make history and history knowledge meaningful. Additionally, results have implications for tests. Assessments should be mindful of cultural validity of items and become more inclusive; perhaps aligning with a more culturally relevant curriculum.