218 research outputs found
Can Grassroots Organizations Reduce Support for Right-Wing Populism via Social Media?
The rise of right-wing populism throughout Western democracies coincided with an increasing adoption of social media – both among supporters and opponents of right-wing populism alike. In light of these trends, we assess whether grassroots organizations are effective in combating right-wing populism via social media. We study this question using a tightly controlled online field experiment embedded in the Facebook campaign of a German grassroots organization. Leveraging geo-spatial variation in where the organization disseminated its Facebook ads targeting Germany’s leading right-wing populist party (AfD), we find that the campaign did not significantly affect the AfD’s vote share and turnout. Drawing on data from a complementary online experiment, we show that insufficient outreach on Facebook together with the absence of individual-level responses of attitudes and behavior explains why the campaign did not meaningfully shape aggregate election outcomes
Female Education and Social Change
Does access to education facilitate the emergence of a human capital elite from which social activists, and thus, social change can emerge? Assembling a city-level panel of the political, intellectual, and economic elite throughout German history, we find that the opening of schools providing secondary education for women increased their representation among the human capital elite. These elites challenged the status quo and developed critical ideas that resonated in cities with higher human capital, connecting women to form a social movement. We find no evidence of other city-specific indicators of economic and gender-specific cultural change affecting our results. Differential returns to education are also unrelated to the increasing representation of women among the human capital elite, as the opening of gender-specific schools has no impact on the opposite gender
Automated verification of model transformations based on visual contracts
The final publication is available at Springer via http://dx.doi.org/10.1007/s10515-012-0102-yModel-Driven Engineering promotes the use of models to conduct the different phases of the software development. In this way, models are transformed between different languages and notations until code is generated for the final application. Hence, the construction of correct Model-to-Model (M2M) transformations becomes a crucial aspect in this approach.
Even though many languages and tools have been proposed to build and execute M2M transformations, there is scarce support to specify correctness requirements for such transformations in an implementation-independent way, i.e., irrespective of the actual transformation language used.
In this paper we fill this gap by proposing a declarative language for the specification of visual contracts, enabling the verification of transformations defined with any transformation language. The verification is performed by compiling the contracts into QVT to detect disconformities of transformation results with respect to the contracts. As a proof of concept, we also report on a graphical modeling environment for the specification of contracts, and on its use for the verification of transformations in several case studies.This work has been funded by the Austrian Science Fund (FWF) under grant P21374-N13,
the Spanish Ministry of Science under grants TIN2008-02081 and TIN2011-24139, and the
R&D programme of the Madrid Region under project S2009/TIC-1650
Продовження напрацювань QUAERE після офіційного завершення проекту: персональний вимір
Впродовж 2016-2018 рр. у рамках проекту Еразмус+ КА2 «QUAERE: Система забезпечення якості освіти в Україні: розвиток на основі європейських стандартів та рекомендацій» було напрацьовано багато того, що має бути продовжене і стає у нагоді при забезпеченні якості вищої освіти в Україні
Lost in translation: On the impact of data coding on penalized regression with interactions
Penalized regression approaches are standard tools in quantitative genetics.
It is known that the fit of an \emph{ordinary least squares} (OLS) regression
is independent of certain transformations of the coding of the predictor
variables, and that the standard mixed model \emph{ridge regression best linear
unbiased prediction} (RRBLUP) is neither affected by translations of the
variable coding, nor by global scaling. However, it has been reported that an
extended version of this mixed model, which incorporates interactions by
products of markers as additional predictor variables is affected by
translations of the marker coding. In this work, we identify the cause of this
loss of invariance in a general context of penalized regression on polynomials
in the predictor variables. We show that in most cases, translating the coding
of the predictor variables has an impact on effect estimates, with an exception
when only the size of the coefficients of monomials of highest total degree are
penalized. The invariance of RRBLUP can thus be considered as a special case of
this setting, with a polynomial of total degree 1, where the size of the fixed
effect (total degree 0) is not penalized but all coefficients of monomials of
total degree 1 are. The extended RRBLUP, which includes interactions, is not
invariant to translations because it does not only penalize interactions (total
degree 2), but also additive effects (total degree 1). Our observations are not
restricted to ridge regression, but generally valid for penalized regressions,
for instance also for the penalty of LASSO
A generalized approach to model the spectra and radiation dose rate of solar particle events on the surface of Mars
For future human missions to Mars, it is important to study the surface
radiation environment during extreme and elevated conditions. In the long term,
it is mainly Galactic Cosmic Rays (GCRs) modulated by solar activity that
contributes to the radiation on the surface of Mars, but intense solar
energetic particle (SEP) events may induce acute health effects. Such events
may enhance the radiation level significantly and should be detected as
immediately as possible to prevent severe damage to humans and equipment.
However, the energetic particle environment on the Martian surface is
significantly different from that in deep space due to the influence of the
Martian atmosphere. Depending on the intensity and shape of the original solar
particle spectra as well as particle types, the surface spectra may induce
entirely different radiation effects. In order to give immediate and accurate
alerts while avoiding unnecessary ones, it is important to model and well
understand the atmospheric effect on the incoming SEPs including both protons
and helium ions. In this paper, we have developed a generalized approach to
quickly model the surface response of any given incoming proton/helium ion
spectra and have applied it to a set of historical large solar events thus
providing insights into the possible variety of surface radiation environments
that may be induced during SEP events. Based on the statistical study of more
than 30 significant solar events, we have obtained an empirical model for
estimating the surface dose rate directly from the intensities of a power-law
SEP spectra
Effectiveness and cost-efficiency of phosphate binders in hemodialysis
Health political background: In 2006, the prevalence of chronic renal insufficiency in Germany was 91,718, of which 66,508 patients were on dialysis. The tendency is clearly growing. Scientific background: Chronic renal insufficiency results in a disturbance of the mineral balance. It leads to hyperphosphataemia, which is the strongest independent risk factor for mortality in renal patients. Usually, a reduction in the phosphate intake through nutrition and the amount of phosphate filtered out during dialysis are not sufficient to reduce the serum phosphate values to the recommended value. Therefore, phosphate binders are used to bind ingested phosphate in the digestive tract in order to lower the phosphate concentration in the serum. Four different groups of phosphate binders are available: calcium- and aluminium salts are the traditional therapies. Sevelamer and Lanthanum are recent developments on the market. In varying doses, all phosphate binders are able to effectively lower phosphate concentrations. However, drug therapies have achieved recommended phosphate levels in only 50 percent of patients during the last years. Research questions: How effective and efficient are the different phosphate binders in chronic renal insufficient patients? Methods: The systematic literature search yielded 1,251 abstracts. Following a two-part selection process with predefined criteria 18 publications were included in the assessment. Results: All studies evaluated conclude that serum phosphate, serum calcium and intact parathyroid hormone can be controlled effectively with all phosphate binders. Only the number of episodes of hypercalcaemia is higher when using calcium-containing phosphatebinders compared to Sevelamer and Lanthanum. Regarding the mortality rate, the cardiovascular artery calcification and bone metabolism no definite conclusions can be drawn. In any case, the amount of calcification at study start seems to be crucial for the further development of the cardiovascular calcification. Economic studies show higher costs for Sevelamer and Lanthanum compared to calcium-containing phosphate binders. Discussion: Only a few well documented primary studies on the effectiveness of phosphate binders are available. Particularly long-term studies with a robust study design and transparent documentation are lacking. Ten of the eleven primary studies included in this report were conducted in only 539 patients from five patient collectives. Conclusions: From a medical point of view, Sevelamer shows some superiority over calcium-containing phosphate binders based on the current data, at least for special indications. The validity of the present Health Technology Assessment (HTA) report is significantly limited due to the limited number of available publications, the low sample size of treated patients, as well as the fact that the majority of studies are based on the same patient collectives. Prospective long-term studies not funded by the industry with adequate sample sizes and comparable study designs are called for to make authoritative statements regarding the medical effectiveness and safety of Sevelamer and Lanthanum, as well as regarding their economic efficiency
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