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941.
The measurement of urbanization rates and other uses of statistical information, for example the use of historical town growth to measure long-term economic growth, are usually based on an ad hoc population threshold to define and practically classify settlements as towns. The method, however, trades off accuracy and precision for convenience and simplicity. This paper proposes a new threshold that uses the town size distribution together with agricultural data to derive an appropriate cutoff value. The relevance of agricultural income is integrated into the classification scheme through the differential effect of local agricultural endowments on settlement size. The threshold is chosen such that the size of towns above the cutoff is statistically not influenced by local agricultural endowments, while the size of villages, which is below the threshold, is indeed shaped by them. This new approach is practically demonstrated with an application to the urban system of the nineteenth century in the German region of Saxony. This setting is used to investigate the relevance of a different classification for the development of urbanization over time and Gibrat’s law. The results demonstrate that the underlying classification scheme matters strongly for the conclusions drawn from historical urban data. They also indicate that the use of a common population threshold for a comparative analysis or temporal comparisons in a historical context increases the misclassifications of settlements.  相似文献   
942.
As has been seen in other contexts, workers in similar occupations earned much higher wages in Canada than Europe during the 1920s. This observation and related aspects of immigration are addressed with a life-cycle model of the migration decision. The characteristics of immigrants from five European countries: Ireland, Italy, the Netherlands, Poland, and Sweden, are explored in a way that sheds light not just on those population flows but on the process of immigration generally. We draw on passenger manifests from immigrant ships for information on the individual migrants. Simulations, based partly on the these manifests, reveal that the costs of migration, borrowing constraints, concern for status, and country-specific taste preferences account for key immigrant characteristics, and help explain the large wage differentials that persisted despite Canada’s relatively open immigration policy.  相似文献   
943.
In 2015, the Federal Communications Commission (FCC) imposed common carriage regulation—so-called Title II requirements—on previously unregulated broadband Internet service providers. The regime shift was premised on the FCC’s findings that such rules had demonstrably yielded economic gains. This paper evaluates the FCC’s empirical arguments and finds them uncompelling. Adjustments for inflation or general economic trends eliminate the effects cited by the FCC. Moreover, contrary to the Commission’s assessment, mobile services and broadband markets have shown notable growth in response to deregulatory events that reduce Title II requirements.  相似文献   
944.
The legal framing of a firm’s pricing strategy can determine whether it constitutes online resale price maintenance (RPM) or online most favored nation (MFN). Together, cases that involve online RPM and MFN can be viewed as a natural experiment of how antitrust economics and law may adapt to an online world. Thus far, legal theories that have been inconsistent with economic theories have dictated enforcement across jurisdictions, which has led to confusion that thwarts potentially efficient business practices. This paper distinguishes issues of online RPM from traditional RPM and online RPM from online MFN. We apply the economics learning to RPM and analyze the antitrust cases of online RPM and MFN to date in the United States, Europe, and Australia. Finally, we offer policy recommendations that reduce the confusion in current legal doctrine.  相似文献   
945.
The starting point of this paper is a January 1977 judgment of the Indian Supreme Court, which applied the rule of reason to vertical restraints and anticipated many of the arguments of the Sylvania judgment. After summarizing the background of the Indian case, I set out the main points of similarity and difference between the two judgments, and finally assess the somewhat erratic influence of post-Sylvania antitrust thinking on Indian competition law and jurisprudence.  相似文献   
946.
Many studies have shown the importance of the socio-cultural factors that lead girls to desert scientific and technological courses. Over a long period, the contents of the French technology education (TE) college curricula may well have contributed to strengthening the feeling among girls that this discipline was better suited to boys. The choice of technical artifacts that embody the knowledge taught could be partially responsible for this. Our investigation was conducted in two stages. Firstly, we made an inventory of artifacts presented in four TE schoolbooks for the 6th grade. Secondly, we submitted this list to a population of 98 girls and boys (12–14 years). Our results indicate that most of these artifacts were categorized as mixed. However, those that are classed as masculine are more numerous than feminine one’s. They are also more prevalent among girls and their number increases with age. The grouping of these artifacts by families also shows gender differences.  相似文献   
947.
Germany has only very limited domestic energy resources. Seventy percent of primary energy needs must be covered by imports. The markets for energy are marked by a wide diversity and a large number of providers. The oil market has been intensely competitive for decades now. Lignite and hard coal are subjected to fierce substitution competition, especially with natural gas. The natural gas and electricity markets were fully liberalized in 1998. Consumers can freely choose from a vast number of suppliers. Since the beginning of this century, however, state interference particularly in the electricity market has increased. The expansion of renewables has been promoted since the year 2000 by feed-in priority and feed-in remunerations regulated by the state. The energy transition initiated in 2011 is characterized by ambitious energy and climate policy targets. Key pillars include the conversion of electricity generation from production on the basis of conventional energy sources to a system based mainly on renewable energies combined with stringent requirements designed to enhance energy efficiency and what are probably the most ambitious climate protection targets worldwide. As regards the expansion of renewables and the phase-out of nuclear energy, Germany is keeping to its target path. By contrast, there are no signs yet that the objectives formulated in terms of the lowering of primary energy consumption and the reduction in greenhouse gas emissions will be achieved.  相似文献   
948.
Germany’s energy turnaround is leading to an increasing integration of photovoltaics (PVs) throughout its distribution grid. To ensure safe grid operation in times of high solar radiation, PV plants must either be throttled back to comply with the feed-in limitation or store a portion of their excess electricity in batteries. This paper presents a grid-optimized operating strategy for PV storage systems based on a Fuzzy Logic Controller that reduces peak feed-in and thus also PV curtailment losses. The Fuzzy Logic Controller uses data on PV power surplus and battery charge level as input variables. To obtain good results, the set of numerical parameters of the membership functions is enhanced by evolutionary programming.The energetic assessment shows that even small electrical storage capacities (<<5?kWh) reduce curtailment losses considerably when using the grid-optimized operating strategy. The economic assessment shows that, in 2016, investments in PV storage systems with large PV plants and small batteries have small (positive) Internal Rates of Return. The system efficiency of the battery storage has a small impact on the profitability of PV storage systems, whereas the cycle stability and the electricity purchase price have a large impact. Moreover, there is an economic benefit for plant operators to switch from the simple to the grid-optimized operating strategy. Solar forecast inaccuracies and variations in load and generation profiles have a negligible impact on the performance of the control algorithm.  相似文献   
949.
The interaction of centralised and decentralised elements is not only a challenge for the technical und functional implementation of the energy transition, but also for the political and social assignment of developing adequate governance strategies for future energy systems. While “participation” is of capital importance for all governance approaches mediating centralising and decentralising trends, it is far from clear, how participation is to be realized in order to promote energy transition and avoiding pitfalls and flaws of participative decision making processes. Against the backdrop of a multi-dimensional understanding of “participation” comprising procedural, factual, legitimatory and meta-reflective functions, the paper considers the tense relations of participation and efficiency, legitimacy and professionalized expertise, thereby identifying structural challenges for participation in democratic societies. Finally, some suggestions are made, how the governance of the energy transition can be shaped in the future.  相似文献   
950.
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