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901.
902.
903.
In this paper, we examine the ways in which the passage of time is dealt with in econometric studies of violent conflict and civil war with empirical attention to the dynamics of ethnic conflict. We argue that the mainstream approach to econometric studies of civil war is based on a time-invariant ontology and that this is not an appropriate or adequate way of capturing the causal patterns of violent conflict. Based analysis of replication datasets using structural break analysis and rolling windows, we show how careful attention to the passage of time reveals important macro-historical changes in the coefficients on ethnic diversity in explaining conflict incidence. We conclude that econometric studies of civil war need to pay more careful attention to the limitations on the generalizations that they draw through attention to the passage of time and better iteration with qualitative and historical studies.  相似文献   
904.
The paper presents the research results of an investigation into the state of scientific, technological, trade and economic interactions between Russia and Ukraine in terms of their potential, prospects, and problems impeding their cooperation. It is shown that there is a considerable scientific and technological potential both in Russia and Ukraine. Opportunities and conditions for the modernization of both countries’ economies are shown to depend on the coordinated use of their potentials.  相似文献   
905.
Water Resources Management - In river catchments, sediment fluxes facilitate the transport of nutrients and pollutants and reduce water quality, potentially impacting water body health and altering...  相似文献   
906.
907.
This exercise sets up interlinked labor and goods markets in a classroom macroeconomy. Students with worker roles are endowed with labor that can be consumed or sold to firms that post wages, purchase labor, and produce goods that can be either consumed or sold to workers. The money from sales is used by firms to purchase labor in the next period. Complicated record keeping is avoided by using ordinary playing cards to represent money and goods. The exercise can stimulate a discussion of potential output, unemployment, and the role of money in determining wages and prices. Use: This experiment can be used in introductory macroeconomics classes to teach concepts of the circular flow, real and money wages, unemployment, and labor market equilibrium and in intermediate classes to consider Keynesian and quantity theories. Time required: Fifteen minutes for reading instructions, 30 to 45 minutes for trading (depending on the number of periods), and 15 minutes for discussion. Materials: You will need one copy of the instructions for each person and one deck of ordinary playing cards for each replicated group of two workers and one firm. No money or other incentives are required.  相似文献   
908.
C.K. Folkertsma 《De Economist》1999,147(4):461-488
This paper describes a model in which monetary shocks have persistent real effects. Starting from the limited participation model of Christiano (1991) with capital adjustment costs as suggested by Dow (1995) it is confirmed that costs of equipment installation and restrictions on consumer portfolio choices alone cannot account for the observed effects of monetary policy. However, after introducing nominal wage contracts as a third friction, the model generates real effects of monetary shocks. It is shown that these real effects are highly persistent for a realistic size of adjustment costs and strongly autocorrelated money growth shocks which are typical for Europe.  相似文献   
909.
Six years (2009–2015) of temperature and dissolved oxygen profile data show hypoxic conditions are common in the bottom waters of southern Green Bay, Lake Michigan during the summer. Depleted oxygen concentrations (<5?mg?L?1) affect nearly 70% of the 38 stations sampled representing an area of ~500–600?km2. Stratification typically lasts 2+?months, from late June to early September, and some stations exhibit bottom water hypoxia (<2?mg?L?1) at a frequency of nearly 25% when sampled during this period. A monitoring program initiated in 1986 by the Green Bay Metropolitan Sewerage District has provided a 23?year, recreational season record (May–September) of continuous (15?min interval) in situ bottom water oxygen and temperature measurements at the Entrance Light station of the Green Bay navigational channel. The duration of the hypoxic season ranges from 2?weeks to over 3?months at this shallow 7?m offshore site. This variability likely results from a combination of thermal stratification, oxygen consumption in deeper waters of the bay, and physical forcing mechanisms that drive cool, oxygen depleted, bottom waters on a southerly trajectory across this sensor. These data suggest the duration of hypoxic conditions may have increased during the stratified season in recent years. Hypoxia in the bay would also appear to be sensitive to relatively small changes in these forces, particularly changes in organic carbon loading and the duration of stratification.  相似文献   
910.
Indigenous community members along the Slave River in Canada have voiced their concerns for the health of ecosystems under pressure from resource extraction, hydroelectric development and global climate change. We present a test case of traditional knowledge and scientific results about the spawning and migration patterns of fish in the Slave River and Delta. This dual knowledge system approach elucidates the broader connectivity of local study regions and can improve monitoring programmes by extending beyond the usual context/confines of the present or recent past, increasing the spatial and temporal range of system information.  相似文献   
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