Agglomeration economies with consistent productivity estimates

This paper investigates the relative impact of microeconomic agglomeration mechanisms on plant’s total factor productivity (TFP) using German establishment and employment level data. Contrasting different strategies to estimate TFP from plant level production functions reveals that not accounting for the endogeneity of input choices and not separating price effects from true productivity leads to underestimated agglomeration economies. Under the preferred TFP measure, labor market pooling, captured by the correlation of the occupational composition between one county-industry and the rest of the county, is found to have the largest impact. Besides, two knowledge spillover mechanisms, transmitted via job changes and public R&D funding, positively affect plant productivity. Except for job changes the result is even robust when the spatial units are broadened from counties to labor market regions. Testing for urbanization and localization economies, I find that TFP is higher in more specialized and larger counties, whereas sectoral diversity is of no importance at the county level.agglomeration economies, modifiable areal unit problem , TFP estimation, price bias, localization, urbanization economies

Minimum comparable areas for the period 1872–2010: an aggregation of Brazilian municipalities

The number of municipalities in Brazil has risen continually, and consequentially the delineation of spatial units varies substantially over time. The present paper develops a routine for the generation of time-consistent 'Minimum Comparable Areas' (AMC) for any arbitrary sub-period between two census years in the range between the first and last demographic census 1872-2010. It relies on recently compiled material by the Brazilian Institute for Geography and Statistics (IBGE). The corresponding Stata code is provided in the Appendix of the paper. Thus, the developed AMCs are immediately accessible and enable long-term panel studies with regional data.Desde a era imperial, o número de municípios no Brasil tem aumentado contínua e substancialmente. Essas mudanças na delimitação das unidades espaciais representam uma dificuldade para qualquer pesquisa que pretenda utilizar dados regionais de diferentes anos. O presente artigo desenvolve uma rotina para a geração de "Áreas Mínimas Comparáveis" (AMC) consistentes em tempo para qualquer subperíodo arbitrário entre dois anos de censo na faixa entre o primeiro e o último censo demográfico 1872-2010. Baseia-se em material compilado recentemente pelo Instituto Brasileiro de Geografia e Estatística (IBGE). O código correspondente em Stata é fornecido no Apêndice do artigo. Assim, os AMCs desenvolvidos são imediatamente acessíveis e permitem estudos de painel de longo prazo com dados regionais. &nbsp

Ultralong coherence times in the purely electronic zero-phonon line emission of single molecules

We report the observation of ultralong coherence times in the purely electronic zero-phonon line emission of single terrylenediimide molecules at 1.4 K. Vibronic excitation and spectrally resolved detection with a scanning Fabry-Perot spectrum analyzer were used to measure a linewidth of 65 MHz. This is within a factor of 1.6 of the transform limit. It therefore indicates that single molecule emission may be suited for applications in linear optics quantum computation. Additionally it is shown that high resolution spectra taken with the spectrum analyzer allow for the investigation of fast spectral dynamics in the emission of a single molecule.Comment: to appear in Applied Physics Letter

Design Evaluation of the Universalization Fund for Telecommunication Services in Brazil

The Universalization Fund for Telecommunications Services Fust was designed in 2000 to provide public investments to expand services in areas that needed to be better covered by the telecom carries However since its creation the fund lacks effectiveness The study seeks to evaluate this public policy and explain the practically non-existent results and impacts until now Our contribution is to structure this public policy using a logic model and the program theory of change to understand and evaluate the fund s regulatory design The analysis recognizes that the recent changes in Fust s legislation have improved its architecture and governance following suggestions from the international literature on universalization funds Nonetheless some additional regulatory adjustments are suggested such as creating more restrictive mechanisms to block or reallocate the fund s revenues keeping its steering committee active discussing new sources of revenue and improving communication and transparenc

The Rhetorical Crisis of the Fall of the Berlin Wall: Forgotten Narratives and Political Directions

The accidental opening of the Berlin Wall on November 9th, 1989, dismantled the political narratives of the East and the West and opened up a rhetorical arena for political narrators like the East German citizen movements, the West German press, and the West German leadership to define and exploit the political crisis and put forward favorable resolutions. With this dissertation, I trace the neglected and forgotten political directions as they reside in the narratives of the East German citizen movements, the West German press, and the West German political leadership between November 1989 and February 1990. The events surrounding November 9th, 1989, present a unique opportunity for this endeavor in that the common flows of political communication between organized East German publics, the West German press, and West German political leaders changed for a moment and with it the distribution of political legitimacy. To account for these new flows of political communication and the battle between different political crisis narrators over the rhetorical rights to reestablish political legitimacy, I develop a rhetorical model for political crisis narrative. This theoretical model integrates insights from political crisis communication theories, strategic narratives, and rhetoric. My analyses then test this model by tracing the narrative trajectories and rhetorical transformations of the narrative enactments by the East German citizen movements, the West German press, and the West German political leadership. As recent historical research revealed, Helmut Kohl favored what others refers to as the “pre-fabrication model” for German and European unification, which entails the expansion of West German and European legal, political, and economic systems eastward. Using Sarotte’s research about Kohl’s prefab model as a rhetorical anchor, my reconstructions of the different political crisis narratives reveal how the individual narratives support or weaken Helmut Kohl’s pre-fabrication model for German and European reunification. Finally, while the West’s rhetoric of practical politics, economic necessity, and rapid unification offered short-term solutions for political and economic integration, it concealed long-term narrative possibilities for German and European integration. Thus, this dissertation discusses the hidden rhetorical possibility for German and European political integration as they reside within the discourse between the East German opposition groups, the West German press, and the West German political leadership

X-By-Wire via ISOBUS Communication Network

Rosana G. Moreira, Editor-in-Chief; Texas A&M UniversityThis is a paper from International Commission of Agricultural Engineering (CIGR, Commission Internationale du Genie Rural) E-Journal Volume 9 (2007): X-By-Wire via ISOBUS Communication Network. Manuscript ATOE 07 002. Vol. IX. July, 2007

Preface to Special Section "ATOE 2006" of CIGR Ejournal Vol. IX

Rosana G. Moreira, Editor-in-Chief; Texas A&M UniversityThis is a paper from International Commission of Agricultural Engineering (CIGR, Commission Internationale du Genie Rural) E-Journal Volume 9 (2007): Preface to Special Section "ATOE 2006" of CIGR Ejournal Vol. I

Dynamic response studies on aggregation and breakage dynamics of colloidal dispersions in stirred tanks

Aggregation and breakage of aggregates of fully destabilized polystyrene latex particles in turbulent flow was studied experimentally in both batch and continuous stirred tanks using small-angle static light scattering. It was found that the steady-state values of the root-mean-square radius of gyration are fully reversible upon changes of stirring speed as well as solid volume fraction. Steady-state values of the root-mean-square radius of gyration were decreasing with decreasing solid volume fraction as well as with increasing stirring speed. Moreover, it was found that the steady-state structure and shape of the aggregates is not influenced by the applied stirring speed