Unmet goals of tracking: within-track heterogeneity of students' expectations for

Educational systems are often characterized by some form(s) of ability grouping, like tracking. Although substantial variation in the implementation of these practices exists, it is always the aim to improve teaching efficiency by creating homogeneous groups of students in terms of capabilities and performances as well as expected pathways. If students’ expected pathways (university, graduate school, or working) are in line with the goals of tracking, one might presume that these expectations are rather homogeneous within tracks and heterogeneous between tracks. In Flanders (the northern region of Belgium), the educational system consists of four tracks. Many students start out in the most prestigious, academic track. If they fail to gain the necessary credentials, they move to the less esteemed technical and vocational tracks. Therefore, the educational system has been called a 'cascade system'. We presume that this cascade system creates homogeneous expectations in the academic track, though heterogeneous expectations in the technical and vocational tracks. We use data from the International Study of City Youth (ISCY), gathered during the 2013-2014 school year from 2354 pupils of the tenth grade across 30 secondary schools in the city of Ghent, Flanders. Preliminary results suggest that the technical and vocational tracks show more heterogeneity in student’s expectations than the academic track. If tracking does not fulfill the desired goals in some tracks, tracking practices should be questioned as tracking occurs along social and ethnic lines, causing social inequality

Situating Ghent in the ISCY study: the implications of the Flemish tracking system for equity and excellence

Belgium occupies a distinct position in PISA 2012 scores. First, the Belgian educational system belongs to the international top in terms of performance. The top students in Belgium score second highest of all ISCY countries on mathematics. However, Belgian 15-year olds are also among the worst performing students on these tests, scoring only slightly better than students from France, Iceland, Norway, Spain, and USA. No wonder then, that Belgium has the highest level of inequality in achievement of all countries taking part in the ISCY-study, as shown by the spread on the PISA results. The aim of the current paper is to offer explanations for this peculiar position of Flanders by searching for system influences on student performance. First, we will discuss the specificities of the Flemish educational system. Thereafter, we will argue that the Flemish tracking system is one of the most important reasons for the existence of the large performance gap

Onvervulde doelen van tracking: heterogene toekomstverwachtingen van leerlingen binnen de onderwijsvormen

Onderwijssystemen worden vaak gekenmerkt door bepaalde vorm(en) van ‘ability grouping’, zoals een indeling naar onderwijsvormen (ook wel aangeduid als tracking of streaming). Hoewel de praktische invulling van dergelijk groeperen van leerlingen verschilt, is het doel steeds tweevoudig. Ten eerste wordt verondersteld dat het efficiënter is om les te geven aan homogene groepen leerlingen wat betreft hun capaciteiten en prestaties. Ten tweede bereiden de verschillende onderwijsvormen de jongeren voor op een andere toekomst en hebben de verschillende onderwijsvormen een andere finaliteit (doorstromingsgericht of arbeidsmarkt). Indien de toekomstverwachtingen van leerlingen (universiteit, hogeschool of werken) in lijn zijn met de doelstellingen van de onderwijsvormen, zou men verwachten dat deze verwachtingen vrij homogeen zijn binnen de onderwijsvormen en heterogeen ertussen. In Vlaanderen bestaat het onderwijssysteem uit vier onderwijstypes (academisch, artistiek, technisch en beroepsonderwijs), die hiërarchisch geordend zijn. Het welgekende watervaleffect is hier een gevolg van, waarbij studenten eerst proberen om in de hoogst gewaardeerde, academisch georiënteerde onderwijsvormen te slagen en zich na falen heroriënteren naar de meer praktische onderwijsvormen. We verwachten dat dit watervaleffect homogene verwachtingen creëert in de academisch georiënteerde onderwijsvormen en heterogene verwachtingen in de praktisch gerichte onderwijsvormen. We maken gebruik van kwantitatieve gegevens verzameld door de International Study of City Youth (ISCY) tijdens het schooljaar 2013-2014 van 2354 leerlingen van het vierde middelbaar in 30 middelbare scholen in Gent (Vlaanderen). Voorlopige resultaten wijzen erop dat de praktische onderwijsvormen meer heterogeniteit vertonen op vlak van toekomstverwachtingen van de leerlingen dan de academisch gerichte vormen. Indien tracking in het secundair onderwijs niet de gewenste doelen bereikt in bepaalde onderwijsvormen, moet deze praktijk in vraag worden gesteld. Een indeling in onderwijsvormen wordt namelijk gekenmerkt door sociale ongelijkheid

Statistiek

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The development of a juvenile porcine augmented renal clearance model through continuous infusion of lipopolysaccharides : an exploratory study

Augmented renal clearance (ARC) as observed in the critically ill (pediatric) population can have a major impact on the pharmacokinetics and posology of renally excreted drugs. Although sepsis has been described as a major trigger in the development of ARC in human critically ill patients, mechanistic insights on ARC are currently lacking. An appropriate ARC animal model could contribute to reveal these underlying mechanisms. In this exploratory study, a state of ARC was induced in 8-week-old piglets. Conscious piglets were continuously infused over 36 h with lipopolysaccharides (LPS) from Escherichia coli (O111:B4) to induce sepsis and subsequently trigger ARC. To study the dose-dependent effect of LPS on the renal function, three different doses (0.75, 2.0, 5.0 mu g/kg/h) were administered (two male piglets/dose, one sham piglet), in combination with fluid administration (0.9% NaCl) at 6 ml/kg/h. Single boluses of renal markers, i.e., creatinine [40 mg/kg body weight (BW)], iohexol (64.7 mg/kg BW), and para-aminohippuric acid (PAH, 10 mg/kg BW) were administered intravenously to evaluate the effect of LPS on the renal function. Clinical parameters were monitored periodically. Blood sampling was performed to determine the effect on hematology, neutrophil gelatinase-associated lipocalin, and prostaglandin E-2 plasma levels. All piglets that were continuously infused with LPS displayed an elevated body temperature, heart rhythm, and respiratory rate similar to 1-3 h after start of the infusion. After infusion, considerably higher total body clearances of iohexol, creatinine, and PAH were observed, independent of the administration of LPS and/or its dose. Since also the sham piglet, receiving no LPS, demonstrated a comparable increase in renal function, the contribution of fluid administration to the development of ARC should be further evaluated

Stock market’s reactions to revelation of tax evasion: an empirical assessment

Additionally to the financial crisis causing a world recession, Liechtenstein’s financial sector has been challenged by the so-called “Zumwinkel-Affair”, when a whistle-blower sold data of hundreds of tax evaders to international tax authorities. This paper investigates the impact of this affair, separated from the financial crisis, on the daily stock prices of banks from Liechtenstein. An “unconventional” augmented GARCH-model (labelled as “augmented amalGARCH”), which outperforms conventional models, is introduced and analyses the dynamical pattern and other influences on risk and average performance. Besides other findings, it can be concluded that the Zumwinkel-Affair had an (accumulating) effect on risk of stocks, but surprisingly no impact on average stock returns could be detected

Testing gravitational-wave searches with numerical relativity waveforms: Results from the first Numerical INJection Analysis (NINJA) project

The Numerical INJection Analysis (NINJA) project is a collaborative effort between members of the numerical relativity and gravitational-wave data analysis communities. The purpose of NINJA is to study the sensitivity of existing gravitational-wave search algorithms using numerically generated waveforms and to foster closer collaboration between the numerical relativity and data analysis communities. We describe the results of the first NINJA analysis which focused on gravitational waveforms from binary black hole coalescence. Ten numerical relativity groups contributed numerical data which were used to generate a set of gravitational-wave signals. These signals were injected into a simulated data set, designed to mimic the response of the Initial LIGO and Virgo gravitational-wave detectors. Nine groups analysed this data using search and parameter-estimation pipelines. Matched filter algorithms, un-modelled-burst searches and Bayesian parameter-estimation and model-selection algorithms were applied to the data. We report the efficiency of these search methods in detecting the numerical waveforms and measuring their parameters. We describe preliminary comparisons between the different search methods and suggest improvements for future NINJA analyses.Comment: 56 pages, 25 figures; various clarifications; accepted to CQ

On the Challenges and Opportunities in Generative AI

The field of deep generative modeling has grown rapidly and consistently over the years. With the availability of massive amounts of training data coupled with advances in scalable unsupervised learning paradigms, recent large-scale generative models show tremendous promise in synthesizing high-resolution images and text, as well as structured data such as videos and molecules. However, we argue that current large-scale generative AI models do not sufficiently address several fundamental issues that hinder their widespread adoption across domains. In this work, we aim to identify key unresolved challenges in modern generative AI paradigms that should be tackled to further enhance their capabilities, versatility, and reliability. By identifying these challenges, we aim to provide researchers with valuable insights for exploring fruitful research directions, thereby fostering the development of more robust and accessible generative AI solutions

Possible Causes of False General Relativity Violations in Gravitational Wave Observations

General relativity (GR) has proven to be a highly successful theory of gravity since its inception. The theory has thrivingly passed numerous experimental tests, predominantly in weak gravity, low relative speeds, and linear regimes, but also in the strong-field and very low-speed regimes with binary pulsars. Observable gravitational waves (GWs) originate from regions of spacetime where gravity is extremely strong, making them a unique tool for testing GR, in previously inaccessible regions of large curvature, relativistic speeds, and strong gravity. Since their first detection, GWs have been extensively used to test GR, but no deviations have been found so far. Given GR's tremendous success in explaining current astronomical observations and laboratory experiments, accepting any deviation from it requires a very high level of statistical confidence and consistency of the deviation across GW sources. In this paper, we compile a comprehensive list of potential causes that can lead to a false identification of a GR violation in standard tests of GR on data from current and future ground-based GW detectors. These causes include detector noise, signal overlaps, gaps in the data, detector calibration, source model inaccuracy, missing physics in the source and in the underlying environment model, source misidentification, and mismodeling of the astrophysical population. We also provide a rough estimate of when each of these causes will become important for tests of GR for different detector sensitivities. We argue that each of these causes should be thoroughly investigated, quantified, and ruled out before claiming a GR violation in GW observations.Comment: Review article; 1 figure; 1 table; comments welcom