@techreport{CaliendoGoethnerWeissenberger2019, type = {Working Paper}, author = {Caliendo, Marco and Goethner, Maximilian and Weißenberger, Martin}, title = {Entrepreneurial Persistence Beyond Survival: Measurement and Determinants}, series = {CEPA Discussion Papers}, journal = {CEPA Discussion Papers}, number = {11}, issn = {2628-653X}, doi = {10.25932/publishup-43456}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-434563}, year = {2019}, abstract = {Entrepreneurial persistence is demonstrated by an entrepreneur's continued positive maintenance of entrepreneurial motivation and constantly-renewed active engagement in a new business venture despite counter forces or enticing alternatives. It is thus a crucial factor for entrepreneurs when pursuing and exploiting their business opportunities and to realize potential economic gains and benefits. Using rich data on a representative sample of German business founders, we investigate the determinants of entrepreneurial persistence. Next to observed survival we also construct a hybrid persistence measure capturing also the motivational dimension of persistence. We analyze the influence of individual-level (human capital and personality) and business-related characteristics on both measures as well as their relative importance. We find that the two indicators emphasize different aspects of persistence. For the survival indicator, the predictive power is concentrated in business characteristics and human capital, while for hybrid persistence, the dominant factors are business characteristics and personality. Finally, we show that results are heterogeneous across subgroups. In particular, formerly-unemployed founders do not differ in survival chances, but they are more likely to lack a high psychological commitment to their business ventures.}, language = {en} } @article{CescaSenDahm2014, author = {Cesca, Simone and Sen, Ali Tolga and Dahm, Torsten}, title = {Seismicity monitoring by cluster analysis of moment tensors}, series = {Geophysical journal international}, volume = {196}, journal = {Geophysical journal international}, number = {3}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0956-540X}, doi = {10.1093/gji/ggt492}, pages = {1813 -- 1826}, year = {2014}, abstract = {We suggest a new clustering approach to classify focal mechanisms from large moment tensor catalogues, with the purpose of automatically identify families of earthquakes with similar source geometry, recognize the orientation of most active faults, and detect temporal variations of the rupture processes. The approach differs in comparison to waveform similarity methods since clusters are detected even if they occur in large spatial distances. This approach is particularly helpful to analyse large moment tensor catalogues, as in microseismicity applications, where a manual analysis and classification is not feasible. A flexible algorithm is here proposed: it can handle different metrics, norms, and focal mechanism representations. In particular, the method can handle full moment tensor or constrained source model catalogues, for which different metrics are suggested. The method can account for variable uncertainties of different moment tensor components. We verify the method with synthetic catalogues. An application to real data from mining induced seismicity illustrates possible applications of the method and demonstrate the cluster detection and event classification performance with different moment tensor catalogues. Results proof that main earthquake source types occur on spatially separated faults, and that temporal changes in the number and characterization of focal mechanism clusters are detected. We suggest that moment tensor clustering can help assessing time dependent hazard in mines.}, language = {en} } @article{FossenMartin2018, author = {Fossen, Frank M. and Martin, Thorsten}, title = {Entrepreneurial dynamics over space and time}, series = {Regional science and urban economics}, volume = {70}, journal = {Regional science and urban economics}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0166-0462}, doi = {10.1016/j.regsciurbeco.2018.04.004}, pages = {204 -- 214}, year = {2018}, abstract = {Entrepreneurship is a regional and persistent phenomenon. We jointly investigate spatial dependence and serial dynamics of new business formation. Using panel data from all 402 German counties for 1996-2011, we estimate dynamic spatial panel data models of start-up activity in the high-tech and manufacturing industries. We consider regions of different sizes and systematically search for the most suitable spatial weights matrices. We find substantial spatial dependence as well as time persistence of start-up activity, especially in the high-tech industry. This suggests that local start-up activity has positive extemal effects and that entrepreneurship policy could play an efficiency-enhancing role.}, language = {en} } @article{PetersenNiemzCescaetal.2021, author = {Petersen, Gesa Maria and Niemz, Peter and Cesca, Simone and Mouslopoulou, Vasiliki and Bocchini, Gian Maria}, title = {Clusty, the waveform-based network similarity clustering toolbox}, series = {Geophysical journal international / the Royal Astronomical Society, the Deutsche Geophysikalische Gesellschaft and the European Geophysical Society}, volume = {224}, journal = {Geophysical journal international / the Royal Astronomical Society, the Deutsche Geophysikalische Gesellschaft and the European Geophysical Society}, number = {3}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0956-540X}, doi = {10.1093/gji/ggaa568}, pages = {2044 -- 2059}, year = {2021}, abstract = {Clusty is a new open source toolbox dedicated to earthquake clustering based on waveforms recorded across a network of seismic stations. Its main application is the study of active faults and the detection and characterization of faults and fault networks. By using a density-based clustering approach, earthquakes pertaining to a common fault can be recognized even over long fault segments, and the first-order geometry and extent of active faults can be inferred. Clusty implements multiple techniques to compute a waveform based network similarity from maximum cross-correlation coefficients at multiple stations. The clustering procedure is designed to be transparent and parameters can be easily tuned. It is supported by a number of analysis visualization tools which help to assess the homogeneity within each cluster and the differences among distinct clusters. The toolbox returns graphical representations of the results. A list of representative events and stacked waveforms facilitate further analyses like moment tensor inversion. Results obtained in various frequency bands can be combined to account for large magnitude ranges. Thanks to the simple configuration, the toolbox is easily adaptable to new data sets and to large magnitude ranges. To show the potential of our new toolbox, we apply Clusty to the aftershock sequence of the M-w 6.9 25 October 2018 Zakynthos (Greece) Earthquake. Thanks to the complex tectonic setting at the western termination of the Hellenic Subduction System where multiple faults and faulting styles operate simultaneously, the Zakynthos data set provides an ideal case-study for our clustering analysis toolbox. Our results support the activation of several faults and provide insight into the geometry of faults or fault segments. We identify two large thrust faulting clusters in the vicinity of the main shock and multiple strike-slip clusters to the east, west and south of these clusters. Despite its location within the largest thrust cluster, the main shock does not show a high waveform similarity to any of the clusters. This is consistent with the results of other studies suggesting a complex failure mechanism for the main shock. We propose the existence of conjugated strike-slip faults in the south of the study area. Our waveform similarity based clustering toolbox is able to reveal distinct event clusters which cannot be discriminated based on locations and/or timing only. Additionally, the clustering results allows distinction between fault and auxiliary planes of focal mechanisms and to associate them to known active faults.}, language = {en} } @article{PiontekKalkuhlKriegleretal.2019, author = {Piontek, Franziska and Kalkuhl, Matthias and Kriegler, Elmar and Schultes, Anselm and Leimbach, Marian and Edenhofer, Ottmar and Bauer, Nico}, title = {Economic Growth Effects of Alternative Climate Change Impact Channels in Economic Modeling}, series = {Environmental \& resource economics : the official journal of the European Association of Environmental and Resource Economists}, volume = {73}, journal = {Environmental \& resource economics : the official journal of the European Association of Environmental and Resource Economists}, number = {4}, publisher = {Springer}, address = {Dordrecht}, issn = {0924-6460}, doi = {10.1007/s10640-018-00306-7}, pages = {1357 -- 1385}, year = {2019}, abstract = {Despite increasing empirical evidence of strong links between climate and economic growth, there is no established model to describe the dynamics of how different types of climate shocks affect growth patterns. Here we present the first comprehensive, comparative analysis of the long-term dynamics of one-time, temporary climate shocks on production factors, and factor productivity, respectively, in a Ramsey-type growth model. Damages acting directly on production factors allow us to study dynamic effects on factor allocation, savings and economic growth. We find that the persistence of impacts on economic activity is smallest for climate shocks directly impacting output, and successively increases for direct damages on capital, loss of labor and productivity shocks, related to different responses in savings rates and factor-specific growth. Recurring shocks lead to large welfare effects and long-term growth effects, directly linked to the persistence of individual shocks. Endogenous savings and shock anticipation both have adaptive effects but do not eliminate differences between impact channels or significantly lower the dissipation time. Accounting for endogenous growth mechanisms increases the effects. We also find strong effects on income shares, important for distributional implications. This work fosters conceptual understanding of impact dynamics in growth models, opening options for links to empirics.}, language = {en} }