Sickness presenteeism of German teachers: prevalence and influencing factors

The aim of the present study was to investigate teachers’ sickness presenteeism (SP). We examined the prevalence of SP in a sample of teachers as well as work-related and health-related influencing factors of teachers’ SP. We used a cross-sectional study design. Teachers working at different types of schools in Rhineland-Palatinate (Germany) participated in an online survey. We used Pearson’s Chi-squared test (in case of categorical variables) or Mann–Whitney-U-test (in case of continuous variables) to test for differences between SP and sociodemographic/work-related/health-related factors. Factors influencing SP were identified using multivariable logistic regression analyses. Nine hundred and twenty-four teachers working at 42 different schools completed the questionnaire (response proportion: 50.1%). The prevalence of SP in our study was 57.1%. The multivariable logistic regression analyses showed less support by supervisors (aOR: 1.77; 95-CI: 1.21–2.60), inappropriate administration efforts (aOR: 1.56; 95-CI: 1.16–2.11), and inappropriate recognition of performance (aOR: 1.44; 95-CI: 1.04–198) as well as exhaustion/fatigue (aOR: 2.29; 95-CI: 1.71–3.08) as main predictors of teachers’ SP. SP is widespread among teachers. As SP is associated with impairment of psychological and physical health in the long run, it is important to implement measures to reduce SP. A climate of support and cooperation as well as assistance for ill teachers to deal with work missed due to absence might be useful strategies.     

One hundred and fifty years of sprint and distance running – Past trends and future prospects

Sprint and distance running have experienced remarkable performance improvements over the past century. Attempts to forecast running performances share an almost similarly long history but have relied so far on relatively short data series. Here, we compile a comprehensive set of season-best performances for eight Olympically contested running events. With this data set, we conduct (1) an exponential time series analysis and (2) a power-law experience curve analysis to quantify the rate of past performance improvements and to forecast future performances until the year 2100. We find that the sprint and distance running performances of women and men improve exponentially with time and converge at yearly rates of 4% ± 3% and 2% ± 2%, respectively, towards their asymptotic limits. Running performances can also be modelled with the experience curve approach, yielding learning rates of 3% ± 1% and 6% ± 2% for the women's and men's events, respectively. Long-term trends suggest that: (1) women will continue to run 10–20% slower than men, (2) 9.50 s over 100 m dash may only be broken at the end of this century and (3) several middle- and long-distance records may be broken within the next two to three decades. The prospects of witnessing a sub-2 hour marathon before 2100 remain inconclusive. Our results should be interpreted cautiously as forecasting human behaviour is intrinsically uncertain. The future season-best sprint and distance running performances will continue to scatter around the trends identified here and may yield unexpected improvements of standing world records.     

Cognitive and environmental predictors of early literacy skills

Not all young children benefit from book exposure in preschool age. It is claimed that the ability to hold information in mind (short-term memory), to ignore distraction (inhibition), and to focus attention and stay focused (sustained attention) may have a moderating effect on children’s reactions to the home literacy environment. In a group of 228 junior kindergarten children with a native Dutch background, with a mean age of 54.29 months (SD = 2.12 months), we explored therefore the relationship between book exposure, cognitive control and early literacy skills. Parents filled in a HLE questionnaire (book sharing frequency and an author recognition checklist as indicator of parental leisure reading habits), and children completed several tests in individual sessions with the researcher (a book-cover recognition test, PPVT, letter knowledge test, the subtests categories and patterns of the SON, and cognitive control measures namely digit span of the KABC, a peg tapping task and sustained attention of the ANT). Main findings were: (1) Children’s storybook knowledge mediated the relationship between home literacy environment and literacy skills. (2) Both vocabulary and letter knowledge were predicted by book exposure. (3) Short-term memory predicted vocabulary over and above book exposure. (4) None of the cognitive control mechanisms moderated the beneficial effects of book exposure.     

Development of feedforward control in a dynamic manual tracking task

To examine the development of feedforward control during manual tracking, 117 participants in 5 age groups (6 to 7, 8 to 9, 10 to 11, 12 to 14, and 15 to 17 years) tracked an accelerating dot presented on a monitor by moving an electronic pen on a digitizer. To remain successful at higher target velocities, they had to create a predictive model of the target's motion. The ability to track the target at higher velocities increased, and the application of a feedback-based step-and-hold strategy decreased with age, as shown by increases in maximum target velocity and decreases in number of stops between ages 6–7 and 8–9 and between ages 8–9 and 10–11. The ability to exploit feedforward control in a dynamic tracking task improves significantly with age.     

Who likes to engage in writing? – The role of children’s beliefs and intrinsic value regarding leisure writing

Abstract

While leisure writing may help children to acquire writing skills, it can also be considered as an inherently valuable cultural activity. This study explores how children’s beliefs may explain to what extent children are inclined to leisure writing and if there are any gender differences. Building on preliminary scale development work, we analysed data from 963 third-graders. Variables included (a) the intrinsic value attached to leisure writing (b) preceding behavioural, normative, and control beliefs related to these activities, and (c) the level of leisure writing. In a structural equation model, the preceding beliefs were applied as explanatory variables for the intrinsic value. Intrinsic value, in turn, explained a large proportion of variance in children’s leisure-writing activities. Gender differences in leisure writing were mediated by intrinsic value. Significance of intrinsic value and preceding beliefs regarding leisure-writing activities are discussed.     

Dynamische Probleml?sekompetenz

This article is about the importance and validity of dynamic problem solving (DPS) in predicting technical problem solving performances. In addition to DPS, fluid intelligence and technical knowledge were included in the study. Assessing DPS and fluid intelligence simultaneously also allowed for testing the empirical distinction between both constructs. Results are based on data of a sample of car mechatronics (n?=?129) and electronics technicians (n?=?88) and showed that DPS and fluid intelligence were empirically separable. In the first sample (electronics technicians) DPS explained technical problem solving performance best, although fluid intelligence showed incremental validity too. In the second sample (car mechatronics) fluid intelligence was weakly related to the criterion whereas DPS was not at all. When technical knowledge was added to the prediction, both DPS and fluid intelligence did not predict technical problem solving performance. However, in the sample of the electronics technicians fluid intelligence indirectly affected the criterion through technical knowledge. A discussion of the somewhat contradictory results, the different results patterns in the two samples and a theoretical explanation of the results are provided.     

A learning optimizer for a federated database management system

Anfrageoptimierer in modernen Datenbanksystemen (DBS) verwenden ein Kostenmodell, um für eine Anfrage einen effizienten Zugriffsplan aus der Menge aller m?glichen Zugriffspl?ne auszuw?hlen. Die Genauigkeit, mit der diese Kosten gesch?tzt werden, h?ngt stark davon ab, wie genau Statistiken über die Datenverteilung die ihnen zugrunde liegenden Daten modellieren. Veraltete Statistiken, oder ungültige Annahmen im statistischen Modell, führen h?ufig zur Auswahl suboptimaler Zugriffspl?ne und dadurch zu Defiziten bei der Ausführungsgeschwindigkeit von Datenbankanfragen. F?derierte Systeme müssen auf dem koordinierenden DBS Statistiken über verteilte Daten unterhalten, um effiziente Zugriffspl?ne zu entwickeln, wenn Daten aus verschiedenen Datenquellen zusammengeführt werden. Fehlerhafte Statistiken verursachen in diesem Fall schlechte Lastenverteilung sowie zus?tzlichen Kommunikationsaufwand und Netzlast. Die Synchronisation dieser zus?tzlichen Statistiken mit den Statistiken der entfernten Datenquellen ist problematisch, da Datenquellen v?llig unabh?ngig voneinander sind und ihre Statistiken eventuell nicht externalisieren oder inkompatible bzw. andere statistische Modelle verwenden als das koordinierende DBS. Im folgenden zeigen wir eine Erweiterung der Feedback-Schleife von DB2s lernendem Optimierer (LEO) auf f?derierte Architekturen, die es LEO erm?glicht, automatisch Statistiken über Daten auf entfernten Datenquellen zu lernen und zu verwalten. Wir diskutieren mehrere M?glichkeiten, Feedback für f?derierte Anfragen zu erhalten und stellen einen L?sung vor, die lokales Feedback verwendet, und einen Stichprobenprozess (statistical sampling) zu steuren, der die ben?tigten entfernten Daten basierend auf dem Feedback effizient ermittelt. Mittels einer detaillierten Leistungsanalyse der vorgestellten M?glichkeiten im Rahmen einer Fallstudie belegen wir, dass der potenzielle Geschwindigkeitszuwachs für Datenbankanfragen sehr hoch ist, w?hrend die Zusatzbelastung durch LEO in moderaten Grenzen liegt.