Time filter

Source Type

Geiss C.,German Aerospace Center | Geiss C.,Humboldt University of Berlin | Taubenbock H.,German Aerospace Center | Tyagunov S.,German Research Center for Geosciences | And 3 more authors.
Earthquake Spectra | Year: 2014

This paper quantitatively evaluates the suitability of multi-sensor remote sensing to assess the seismic vulnerability of buildings for the example city of Padang, Indonesia. Features are derived from remote sensing data to characterize the urban environment and are subsequently combined with in situ observations. Machine learning approaches are deployed in a sequential way to identify meaningful sets of features that are suitable to predict seismic vulnerability levels of buildings. When assessing the vulnerability level according to a scoring method, the overall mean absolute percentage error is 10.6%, if using a supervised support vector regression approach. When predicting EMS-98 classes, the results show an overall accuracy of 65.4% and a kappa statistic of 0.36, if using a naive Bayes learning scheme. This study shows potential for a rapid screening assessment of large areas that should be explored further in the future. © 2014, Earthquake Engineering Research Institute. Source

Sowa F.,Institute for Employment Research IAB
Polar Record | Year: 2015

In recent years, a decline in the consumption of local foods (kalaalimernit) can be observed in Greenland. However, its appreciation and symbolisation is increasing and kalaalimernit are a powerful contemporary symbol for being Greenlandic. The present article argues that kalaalimernit, as a specifically Greenlandic taste, are suited to marking and maintaining a cultural boundary in relation to the Danish people living in the country, a boundary constructed through identity politics. As the empirical findings from fieldwork conducted in the Greenlandic capital Nuuk and the small coastal settlement Oqaatsut demonstrate, this construction is subject to social change. Greenlanders advocate two different narrative patterns regarding how kalaalimernit are to be understood that stem from contemporary definitional struggles over what kind of cultural boundary is deemed important to demarcate. The struggle illustrates two different perceptions of Greenland as either an indigenous people and/or a small Nordic nation. Copyright © Cambridge University Press 2014. Source

Patuelli R.,University of Lugano | Patuelli R.,The Rimini Center for Economic Analysis | Reggiani A.,University of Bologna | Nijkamp P.,VU University Amsterdam | Schanne N.,Institute for Employment Research IAB
Journal of Geographical Systems | Year: 2011

In this paper, we present a review of various computational experiments concerning neural network (NN) models developed for regional employment forecasting. NNs are nowadays widely used in several fields because of their flexible specification structure. A series of NN experiments is presented in the paper, using two data sets on German NUTS-3 districts. Individual forecasts are computed by our models for each district in order to answer the following question: How relevant are NN parameters in comparison to NN structure? Comprehensive testing of these parameters is limited in the literature. Building on different specifications of NN models-in terms of explanatory variables and NN structures-we propose a systematic choice of NN learning parameters and internal functions by means of a sensitivity analysis. Our results show that different combinations of NN parameters provide significantly varying statistical performance and forecasting power. Finally, we note that the sets of parameters chosen for a given model specification cannot be light-heartedly applied to different or more complex models. © 2010 Springer-Verlag. Source

Patuelli R.,University of Bologna | Patuelli R.,The Rimini Center for Economic Analysis | Schanne N.,Institute for Employment Research IAB | Griffith D.A.,University of Texas at Dallas | And 2 more authors.
Journal of Regional Science | Year: 2012

The geographical distribution and persistence of regional/local unemployment rates in heterogeneous economies (such as Germany) have been, in recent years, the subject of various theoretical and empirical studies. Several researchers have shown an interest in analyzing the dynamic adjustment processes of unemployment and the average degree of dependence of the current unemployment rates or gross domestic product from the ones observed in the past. In this paper, we present a new econometric approach to the study of regional unemployment persistence, in order to account for spatial heterogeneity and/or spatial autocorrelation in both the levels and the dynamics of unemployment. First, we propose an econometric procedure suggesting the use of spatial filtering techniques as a substitute for fixed effects in a panel estimation framework. The spatial filter computed here is a proxy for spatially distributed region-specific information (e.g., the endowment of natural resources, or the size of the "home market") that is usually incorporated in the fixed effects coefficients. The advantages of our proposed procedure are that the spatial filter, by incorporating region-specific information that generates spatial autocorrelation, frees up degrees of freedom, simultaneously corrects for time-stable spatial autocorrelation in the residuals, and provides insights about the spatial patterns in regional adjustment processes. We present several experiments in order to investigate the spatial pattern of the heterogeneous autoregressive coefficients estimated for unemployment data for German NUTS-3 regions. We find widely heterogeneous but generally high persistence in regional unemployment rates. © 2012, Wiley Periodicals, Inc. Source

Kubis A.,Institute for Employment Research IAB | Schneider L.,Coburg University of Applied Sciences | Schneider L.,Halle Institute for Economic Research IWH
Regional Studies | Year: 2015

Kubis A. and Schneider L. Regional migration, growth and convergence – a spatial dynamic panel model of Germany, Regional Studies. This paper empirically analyses the question of how regional migration affects regional convergence and growth in post-reunification Germany. Addressing the endogeneity of migration and human capital, a dynamic panel data model within the framework of β-convergence is applied, accounting for spatial effects. The regressions indicate that out-migration has a negative but modest effect on regional growth; the expected effect of skill selection is only partly confirmed. In the East German subsample, in-migration increases growth independently of its human capital effect; in West Germany, in-migration lowers growth per se, but this negative impact is offset by the growth-stimulating forces of migrants’ skills. © 2015 Regional Studies Association Source

Discover hidden collaborations