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A Study of Assimilation Bias in Name-Based Sampling of Migrants
The use of personal names for screening is an increasingly popular sampling technique for migrant populations. Although this is often an effective sampling procedure, very little is known about the properties of this method. Based on a large German survey, this article compares characteristics of respondents whose names have been correctly classified as belonging to a migrant population with respondentswho aremigrants and whose names have not been classified as belonging to a migrant population. Although significant differences were found for some variables even with some large effect sizes, the overall bias introduced by name-based sampling (NBS) is small as long as procedures with small false-negative rates are employed
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Ein neues Verfahren für namensbasierte Zufallsstichproben von Migranten
The set of best methods for sampling mi- grant populations includes name-based sampling. So far this is done using either ad-hoc lists or onomastic dictionaries for the classi cation of names. This paper pro- poses a new name-based procedure, which uses a Bayes-classi er for the n-grams of the name. The new procedure is fault-tol- erant of alternate spellings, and also allows the classi cation of names that are not found in dictionaries. It was tested using the names of about 1.600 foreigners in the PASS panel. Finally, a CATI survey based on the new method in Hesse is described
Lateralization of eye use in cuttlefish : opposite direction for anti-predatory and predatory behaviors
© The Author(s), 2016. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Frontiers in Physiology 7 (2016): 620, doi:10.3389/fphys.2016.00620.Vertebrates with laterally placed eyes typically exhibit preferential eye use for ecological activities such as scanning for predators or prey. Processing visual information predominately through the left or right visual field has been associated with specialized function of the left and right brain. Lateralized vertebrates often share a general pattern of lateralized brain function at the population level, whereby the left hemisphere controls routine behaviors and the right hemisphere controls emergency responses. Recent studies have shown evidence of preferential eye use in some invertebrates, but whether the visual fields are predominately associated with specific ecological activities remains untested. We used the European common cuttlefish, Sepia officinalis, to investigate whether the visual field they use is the same, or different, during anti-predatory, and predatory behavior. To test for lateralization of anti-predatory behavior, individual cuttlefish were placed in a new environment with opaque walls, thereby obliging them to choose which eye to orient away from the opaque wall to scan for potential predators (i.e., vigilant scanning). To test for lateralization of predatory behavior, individual cuttlefish were placed in the apex of an isosceles triangular arena and presented with two shrimp in opposite vertexes, thus requiring the cuttlefish to choose between attacking a prey item to the left or to the right of them. Cuttlefish were significantly more likely to favor the left visual field to scan for potential predators and the right visual field for prey attack. Moreover, individual cuttlefish that were leftward directed for vigilant scanning were predominately rightward directed for prey attack. Lateralized individuals also showed faster decision-making when presented with prey simultaneously. Cuttlefish appear to have opposite directions of lateralization for anti-predatory and predatory behavior, suggesting that there is functional specialization of each optic lobe (i.e., brain structures implicated in visual processing). These results are discussed in relation to the role of lateralized brain function and the evolution of population level lateralization.This work was supported by a post-doctoral study grant from the Fyssen Foundation to AS, and by a research grant “Sélavie” from the Fyssen Foundation to CJ-A. The Sholley Foundation provided partial support for the research in Woods Hole
Health Technology Assessment zur medizinischen Wirksamkeit und Kosten-Effektivität der Phototherapeutischen Keratektomiemit dem Excimerlaser bei rezidivierenden Erosionen, Hornhautdystrophien, Hornhautdegenerationen und oberflächlichen Hornhautnarben
Hintergrund und Fragestellung: Die phototherapeutische Keratektomie mit dem Excimer-Laser (PTK) wird bei rezidivierenden Hornhauterosionen, oberflächlichen Hornhautdystrophien, zentralen Hornhautdegenerationen, oberflächlichen Hornhautnarben und -irregularitäten mittlerweile weit verbreitet als Therapie eingesetzt. Beim Großteil der Indikationen gibt es nach Ausschöpfung konservativer Maßnahmen, abgesehen von der Hornhautstichelung bei rezidivierenden Erosionen und der Keratoplastik bei Hornhautdystrophien und Hornhautnarben, keine therapeutischen Alternativen. Bisher wurde die PTK bei diesen Indikationen noch nicht in den Leistungskatalog der GKV aufgenommen. Der vorliegende HTA-Bericht sollte die wissenschaftliche Evidenz zusammentragen, inwiefern der medizinischen Nutzen, die medizinischen Notwendigkeit und die Wirtschaftlichkeit der PTK bei den genannten Indikationen nachgewiesen werden können. --
Synoptic and meteorological drivers of extreme ozone concentrations over Europe
The present work assesses the relationship between local and synoptic
meteorological conditions and surface ozone concentration over Europe in
spring and summer months, during the period 1998–2012 using a new interpolated
data set of observed surface ozone concentrations over the European domain.
Along with local meteorological conditions, the influence of large-scale
atmospheric circulation on surface ozone is addressed through a set of airflow
indices computed with a novel implementation of a grid-by-grid weather type
classification across Europe. Drivers of surface ozone over the full
distribution of maximum daily 8 h average values are investigated, along with
drivers of the extreme high percentiles and exceedances or air quality
guideline thresholds. Three different regression techniques are applied:
multiple linear regression to assess the drivers of maximum daily ozone,
logistic regression to assess the probability of threshold exceedances and
quantile regression to estimate the meteorological influence on extreme
values, as represented by the 95th percentile. The relative importance of the
input parameters (predictors) is assessed by a backward stepwise regression
procedure that allows the identification of the most important predictors in
each model. Spatial patterns of model performance exhibit distinct variations
between regions. The inclusion of the ozone persistence is particularly
relevant over southern Europe. In general, the best model performance is found
over central Europe, where the maximum temperature plays an important role as
a driver of maximum daily ozone as well as its extreme values, especially
during warmer months
Interviewer effects on non-response propensity in longitudinal surveys:a multilevel modelling approach
The paper investigates two different multilevel approaches, the multilevel cross-classified and the multiple-membership models, for the analysis of interviewer effects on wave non-response in longitudinal surveys. The models proposed incorporate both interviewer and area effects to account for the non-hierarchical structure, the influence of potentially more than one interviewer across waves and possible confounding of area and interviewer effects arising from the non-random allocation of interviewers across areas. The methods are compared by using a data set: the UK Family and Children Survey
Unscreened Hartree-Fock calculations for metallic Fe, Co, Ni, and Cu from ab-initio Hamiltonians
Unscreened Hartree-Fock approximation (HFA) calculations for metallic Fe, Co,
Ni, and Cu are presented, by using a quantum-chemical approach. We believe that
these are the first HFA results to have been done for crystalline 3d transition
metals. Our approach uses a linearized muffin-tin orbital calculation to
determine Bloch functions for the Hartree one-particle Hamiltonian, and from
these obtains maximally localized Wannier functions, using a method proposed by
Marzari and Vanderbilt. Within this Wannier basis all relevant one-particle and
two-particle Coulomb matrix elements are calculated. The resulting
second-quantized multi-band Hamiltonian with ab-initio parameters is studied
within the simplest many-body approximation, namely the unscreened,
self-consistent HFA, which takes into account exact exchange and is free of
self-interactions. Although the d-bands sit considerably lower within HFA than
within the local (spin) density approximation L(S)DA, the exchange splitting
and magnetic moments for ferromagnetic Fe, Co, and Ni are only slightly larger
in HFA than what is obtained either experimentally or within LSDA. The HFA
total energies are lower than the corresponding LSDA calculations. We believe
that this same approach can be easily extended to include more sophisticated
ab-initio many-body treatments of the electronic structure of solids.Comment: 11 papes, 7 figures, 5 table
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