University of Mannheim

About: University of Mannheim is a education organization based out in Mannheim, Germany. It is known for research contribution in the topics: Population & European union. The organization has 4448 authors who have published 12918 publications receiving 446557 citations. The organization is also known as: Uni Mannheim & UMA.

Fast Summation at Nonequispaced Knots by NFFT

Abstract: We develop a new algorithm for the fast computation of discrete sums $f(y_j) := \sum_{k=1}^N \alpha_k K(y_j-x_k)$ (j =1, . . ., M) based on the recently developed fast Fourier transform (FFT) at nonequispaced knots. Our algorithm, in particular our regularization procedure, is simply structured and can be easily adapted to different kernels K. Our method utilizes the widely known FFT and can consequently incorporate advanced FFT implementations. In summary, it requires ${\cal O} (N \log N +M)$ arithmetic operations. We prove error estimates to obtain clues about the choice of the involved parameters and present numerical examples in one and two dimensions.

Refugees Unwelcome? Changes in the Public Acceptance of Immigrants and Refugees in Germany in the Course of Europe’s ‘Immigration Crisis’

Abstract: Based on an innovative design, combining a multi-factorial survey experiment with a longitudinal perspective, we examine changes in the public acceptance of immigrants in Germany from the beginning of the so-called ‘migration crisis’ to after the sexual assaults of New Year’s Eve (NYE) 2015/2016. In contrast to previous studies investigating similar research questions, our approach allows to differentiate changes along various immigrant characteristics. Derived from discussions making up the German immigration discourse during this time, we expect reduced acceptance especially of those immigrants who were explicitly connected to the salient events, like Muslims and the offenders of NYE. Most strikingly, we find that refugees were generally highly accepted and even more so in the second wave, whereas the acceptance of immigrants from Arab or African countries further decreased. Moreover, female respondents’ initial preference for male immigrants disappeared. Contrary to our expectations, we find no changes in the acceptance of Muslims. We conclude that (i) public opinion research is well advised to match the particular political and social context under investigation to a fitting outcome variable to adequately capture the dynamics of anti-immigrant sentiment and that (ii) the vividly discussed upper limits for refugees seem to be contrary to public demands according to our data.

What does a nation owe non-citizens? National attachments, perception of threat and attitudes towards granting citizenship rights in a comparative perspective

Abstract: In this article we test the effects of national attachments (patriotism and chauvinism) and perception of threat on citizens' willingness to concede citizenship rights to immigrants in France, Germany (West and East), the USA and Israel. Our findings show that despite marked differences in countries' migration policies and conceptions of nationhood, no significant differences were found in attitudes towards the allocation of citizenship rights to immigrants. Furthermore, our analysis suggests that contrary to our expectations, 1) the effects of both chauvinism and patriotism on willingness to grant citizenship rights to immigrants were rather low in Germany and Israel — the two ethno-national states, and strongest in France and the USA — which stand for republican and multicultural models of incorporation, respectively; 2) the effects of threat on exclusion of immigrants from citizenship rights was weaker in Israel (ethnic democracy) but stronger in the liberal democratic countries. In the conclusion, we suggest possible explanations for these rather intriguing and paradoxical findings.

The frequency of family meals and nutritional health in children: a meta-analysis.

Abstract: Findings on the relationship between family meal frequency and children's nutritional health are inconsistent. The reasons for these mixed results have to date remained largely unexplored. This systematic review and meta-analysis of 57 studies (203,706 participants) examines (i) the relationship between family meal frequency and various nutritional health outcomes and (ii) two potential explanations for the inconsistent findings: sociodemographic characteristics and mealtime characteristics. Separate meta-analyses revealed significant associations between higher family meal frequency and better overall diet quality (r = 0.13), more healthy diet (r = 0.10), less unhealthy diet (r = -0.04) and lower body mass index, BMI (r = -0.05). Child's age, country, number of family members present at meals and meal type (i.e. breakfast, lunch or dinner) did not moderate the relationship of meal frequency with healthy diet, unhealthy diet or BMI. Socioeconomic status only moderated the relationship with BMI. The findings show a significant relationship between frequent family meals and better nutritional health - in younger and older children, across countries and socioeconomic groups, and for meals taken with the whole family vs. one parent. Building on these findings, research can now target the causal direction of the relationship between family meal frequency and nutritional health.