We use topic modeling to study research articles in environmental and resource economics journals in the period 2000–2019. Topic modeling based on machine learning allows us to identify and track latent topics in the literature over time and across journals, and further to study the role of different journals in different topics and the changing emphasis on topics in different journals. The most prevalent topics in environmental and resource economics research in this period are growth and sustainable development and theory and methodology. Topics on climate change and energy economics have emerged with the strongest upward trends. When we look at our results across journals, we see that journals have different topical profiles and that many topics mainly appear in one or a few selected journals. Further investigation reveal latent semantic structures across research themes that only the insider would be aware.
Due to the price elasticity of demand for secondhand commodities, it is difficult to establish a quantitative model for the auction. This paper proposes an agent-based multiattribute reverse auction model to support multicommodity combinatorial auction. First, this paper establishes an agent-based reverse auction model and introduces the framework, procedures, and protocols of the model in detail. Second, in light of the multicommodity environment, the targets, protocols, auction strategies, and approaches are identified. Finally, by using the proposed agent-based auction model, both buyers and sellers will reach simultaneous agreements on the details of the commodities to complete the auction. 相似文献
Governments have used deficit policies in recent years, yet many still face fiscal debt problems. Thus, this research uses Range Directional Measure Dynamic Directional Distance Function model with negative data to explore the financial efficiency of local governments in Taiwan from 2011 to 2018. This article has three major contributions: (1) The research uses RDM Dynamic DDF model with negative data to solve the problem of negative values on input and output data and uses dynamic models to make up for the deficiencies of past research. (2) Due to the differences in regions, local governments have different fiscal budgets. Therefore, this article uses the Wilcoxon Test to explore the efficiency differences of local governments in different regions. (3) This article analyzes the impact of central subsidies and government deficits (debts) of local governments on fiscal efficiency, and discusses the efficiency of government fiscal execution. The results are as follows. (1) Seven counties and cities with the best efficiency, and seven local governments with poor efficiency. (2) The fiscal performances of outlying islands and eastern local governments are better than those of western local governments. (3) Kaohsiung City has the highest accumulated debt and Tainan City exhibits poor financial performance. 相似文献