Comparing the MCMC Efficiency of JAGS and Stan for the Multi-Level Intercept-Only Model in the Covariance- and Mean-Based and Classic Parametrization

Bayesian MCMC is a widely used model estimation technique, and software from the BUGS family, such as JAGS, have been popular for over two decades. Recently, Stan entered the market with promises of higher efficiency fueled by advanced and more sophisticated algorithms. With this study, we want to contribute empirical results to the discussion about the sampling efficiency of JAGS and Stan. We conducted three simulation studies in which we varied the number of warmup iterations, the prior informativeness, and sample sizes and employed the multi-level intercept-only model in the covariance- and mean-based and in the classic parametrization. The target outcome was MCMC efficiency measured as effective sample size per second (ESS/s). Based on our specific (and limited) study setup, we found that (1) MCMC efficiency is much higher for the covariance- and mean-based parametrization than for the classic parametrization, (2) Stan clearly outperforms JAGS when the covariance- and mean-based parametrization is used, and that (3) JAGS clearly outperforms Stan when the classic parametrization is used.Peer Reviewe

Automated Test Assembly in R: The eatATA Package

Combining items from an item pool into test forms (test assembly) is a frequent task in psychological and educational testing. Although efficient methods for automated test assembly exist, these are often unknown or unavailable to practitioners. In this paper we present the R package eatATA, which allows using several mixed-integer programming solvers for automated test assembly in R. We describe the general functionality and the common work flow of eatATA using a minimal example. We also provide four more elaborate use cases of automated test assembly: (a) The assembly of multiple test forms for a pilot study; (b) the assembly of blocks of items for a multiple matrix booklet design in the context of a large-scale assessment; (c) the assembly of two linear test forms for individual diagnostic purposes; (d) the assembly of multi-stage testing modules for individual diagnostic purposes. All use cases are accompanied with example item pools and commented R code.Peer Reviewe

Language competencies of immigrant students in Germany - Results of the IQB-Ländervergleich for elementary schools

Sprachliche Kompetenzen in der Verkehrs- und Instruktionssprache Deutsch sind zentral, um im deutschen Bildungssystem erfolgreich zu sein. Die Ergebnisse des IQB-Ländervergleichs 2011 für den Primarbereich belegen erneut, dass Kinder mit Zuwanderungshintergrund beim Kompetenzerwerb benachteiligt sind und das Deutsche weniger gut beherrschen als ihre Altersgenossen und Altersgenossinnen ohne Zuwanderungshintergrund. Der Sprach- und Leseförderung in den Schulen kommt daher gerade für diese Kinder eine zentrale Bedeutung zu. (DIPF/Orig.)Language competencies are crucial for success in the German educational system. The findings from the IQB-Ländervergleich 2011 (federal states comparison test of national educational standards) for elementary schools once again show that students from immigrant families are less proficient in German than their peers from native families. Special support for reading and second language acquisition is therefore needed. (DIPF/Orig.

Aspekte der Testgüte bei der Erfassung schulischer Kompetenzen von Schülerinnen und Schülern mit sonderpädagogischem Förderbedarf

Im Beitrag wurde geprüft, inwieweit die im IQB-Ländervergleich 2011 in der Primarstufe eingesetzten Kompetenztests in Deutsch und Mathematik dazu geeignet sind, auch die Kompetenzen von Schülerinnen und Schülern mit sonderpädagogischem Förderbedarf (SPF) adäquat zu erfassen. Dazu wurden der Anteil fehlender Werte, die Passung des Raschmodells, differenzielle ltemfunktionalität und Korrelationen der Testwerte zwischen den Schülergruppen mit SPF in Förder- und Grundschulen und Kindern ohne SPF analysiert. Die eingesetzten Tests scheinen die schulischen Kompetenzen von Kindern mit SPF reliabel und valide zu erfassen. Allerdings zeigten sich Einschränkungen hinsichtlich der Vergleichbarkeit der Messungen für Kinder in Förderschulen in Mathematik. (DIPF/Orig.)In 2011, students with special educational needs (SEN) were part of the sample of the National Assessment Study (IQB-Ländervergleich 2011) in primary schools. The study examines if the achievement tests in German and Mathematics are also suited to assess SEN students\u27 proficiencies. To evaluate the structural validity of the achievement tests for SEN students in special education and regular schools, missing patterns, the fit of the Rasch model, differential item functioning, and correlations of the test scores were analyzed. Results show that the achievement tests captured the same proficiencies in similar ways for SEN students compared to students without SEN. However, comparability of the achievement tests in Mathematics was reduced for students in special education schools. (DIPF/Orig.

IQB-Bildungstrend 2018

Im Skalenhandbuch werden die Erhebungsinstrumente dokumentiert, die im IQB-Bildungstrend 2018 in den Fächern Mathematik, Biologie, Chemie und Physik in der Sekundarstufe I eingesetzt wurden. Die Bildungstrend-Studien des IQB sind Teil der Gesamtstrategie der Kultusministerkonferenz zum Bildungsmonitoring. Sie werden regelmäßig durchgeführt, um zu überprüfen, inwieweit die Schülerinnen und Schüler in den einzelnen Ländern in der Bundesrepublik Deutschland die in den länderübergreifend verbindlichen Bildungsstandards formulierten Kompetenzziele erreicht haben. Mit dem IQB-Bildungstrend 2018 war es erstmalig möglich, für das Erreichen der Standards im Fach Mathematik und in den naturwissenschaftlichen Fächern in der 9. Jahrgangsstufe Trends zu berichten (Vergleich der Erhebungsjahre 2012 und 2018)

Efficacy and safety of N-acetyl-GED-0507-34-LEVO gel in patients with moderate-to severe facial acne vulgaris: A phase 2B randomised double-blind, vehicle-controlled trial.

Background: Preliminary in vitro and in vivo studies have supported the efficacy of the peroxisome proliferator-activated receptor-γ (PPARγ) modulator N-acetyl-GED-0507-34-LEVO (NAC-GED) for the treatment of acne-inducing sebocyte differentiation, improving sebum composition and controlling the inflammatory process. Objectives: To evaluate the efficacy and safety of NAC-GED (5% and 2%) in patients with moderate-to-severe facial acne vulgaris. Methods: This double-blind phase II randomized controlled clinical trial was conducted at 36 sites in Germany, Italy and Poland. Patients aged 12-30 years with facial acne, an Investigator Global Assessment (IGA) score of 3-4, and an inflammatory and noninflammatory lesion count of 20-100 were randomized to topical application of the study drug (2% or 5%) or placebo (vehicle), once daily for 12 weeks. The co-primary efficacy endpoints were percentage change from baseline in total lesion count (TLC) and IGA success at week 12; the safety endpoints were adverse events (AEs) and serious AEs. This study was registered with EudraCT (2018-003307-19). Results: Between Q1 in 2019 and Q1 in 2020 450 patients [n = 418 (92·9%) IGA 3; n = 32 (7·1%) IGA 4] were randomly assigned to NAC-GED 5% (n = 150), NAC-GED 2% (n = 150) or vehicle (n = 150). The percentage change in TLC reduction was statistically significantly higher in both the NAC-GED 5% [-57·1%, 95% confidence interval (CI) -60·8 to -53·4; P < 0·001] and NAC-GED 2% (-44·7%, 95% CI -49·1 to -40·1; P < 0·001) groups compared with vehicle (-33·9%, 95% CI -37·6 to -30·2). A higher proportion of patients treated with NAC-GED 5% experienced IGA success (45%, 95% CI 38-53) vs. the vehicle group (24%, 95% CI 18-31; P < 0·001). The IGA success rate was 33% in the NAC-GED 2% group (P = not significant vs. vehicle). The percentage of patients who had one or more AEs was 19%, 16% and 19% in the NAC-GED 5%, NAC-GED 2% and vehicle groups, respectively. Conclusions: The topical application of NAC-GED 5% reduced TLC, increased the IGA success rate and was safe for use in patients with acne vulgaris. Thus, NAC-GED, a new PPARγ modulator, showed an effective clinical response. What is already known about this topic? Acne vulgaris, one of the most common dermatological diseases, affects more than 85% of adolescents. There is a medical need for innovative and safe treatment of acne vulgaris. The peroxisome proliferator-activated receptor-γ (PPARγ) is involved in lipid metabolism and specifically in cell differentiation, sebum production and the inflammatory reaction. What does this study add? N-acetyl-GED-0507-34-LEVO (NAC-GED 5%), a PPARγ modulator, significantly improves acne manifestations in patients with moderate-to-severe acne and is safe and well tolerated. The results suggest that the PPARγ receptor is a novel therapeutic target for acne. The results provide a basis for a large phase III trial to assess the effectiveness and safety profile of NAC-GED in combating a disease that afflicts 80-90% of adolescents

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

Measurement of the tt¯tt¯ production cross section in pp collisions at √s=13 TeV with the ATLAS detector

A measurement of four-top-quark production using proton-proton collision data at a centre-of-mass energy of 13 TeV collected by the ATLAS detector at the Large Hadron Collider corresponding to an integrated luminosity of 139 fb−1 is presented. Events are selected if they contain a single lepton (electron or muon) or an opposite-sign lepton pair, in association with multiple jets. The events are categorised according to the number of jets and how likely these are to contain b-hadrons. A multivariate technique is then used to discriminate between signal and background events. The measured four-top-quark production cross section is found to be 26+17−15 fb, with a corresponding observed (expected) significance of 1.9 (1.0) standard deviations over the background-only hypothesis. The result is combined with the previous measurement performed by the ATLAS Collaboration in the multilepton final state. The combined four-top-quark production cross section is measured to be 24+7−6 fb, with a corresponding observed (expected) signal significance of 4.7 (2.6) standard deviations over the background-only predictions. It is consistent within 2.0 standard deviations with the Standard Model expectation of 12.0 ± 2.4 fb

Measurement and interpretation of same-sign W boson pair production in association with two jets in pp collisions at s = 13 TeV with the ATLAS detector

This paper presents the measurement of fducial and diferential cross sections for both the inclusive and electroweak production of a same-sign W-boson pair in association with two jets (W±W±jj) using 139 fb−1 of proton-proton collision data recorded at a centre-of-mass energy of √s = 13 TeV by the ATLAS detector at the Large Hadron Collider. The analysis is performed by selecting two same-charge leptons, electron or muon, and at least two jets with large invariant mass and a large rapidity diference. The measured fducial cross sections for electroweak and inclusive W±W±jj production are 2.92 ± 0.22 (stat.) ± 0.19 (syst.)fb and 3.38±0.22 (stat.)±0.19 (syst.)fb, respectively, in agreement with Standard Model predictions. The measurements are used to constrain anomalous quartic gauge couplings by extracting 95% confdence level intervals on dimension-8 operators. A search for doubly charged Higgs bosons H±± that are produced in vector-boson fusion processes and decay into a same-sign W boson pair is performed. The largest deviation from the Standard Model occurs for an H±± mass near 450 GeV, with a global signifcance of 2.5 standard deviations