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161.
Invertebrate communities from different coastal marsh‐plant communities were compared along wave‐exposure gradients using data from 1994, 1998 and 1999. Data were subjected to correspondence analyses to search for patterns in invertebrate communities in relation to plant‐community structure and wave exposure. In 1994, quantitative plant‐ and sediment‐invertebrate samples were taken from nine habitats: four from inland, subsurface‐connected marshes and five from littoral, emergent marshes. In 1998, sweep‐net samples were taken from 13 plant communities: six on the exposed and seven on the protected side of an island. In 1999, 2–3 plant communities/sites were sampled with sweep nets from four sites around the Bay so that intersite differences between inner, less‐exposed and outer, more‐exposed habitats could be examined. In all three studies, correspondence analyses separated inland, protected or inner sites from littoral, exposed or outer sites, suggesting differences in invertebrate‐community structure. For example, Hydracarina and Asellidae occurred in large numbers in inland sites, but were less common or absent from exposed, littoral sites. Littoral marshes also separated along an exposure gradient with Tanytarsini and Orthocladiinae collectors of organic particles occurring in very high numbers in outer, exposed areas where organic particles from the pelagic zone entered the marsh. Certain plant‐community types clustered together (e.g. wet meadow and Scirpus) while others, such as Typha, stands clustered according to exposure to waves suggesting the importance of both plant‐community structure and wave exposure in determining invertebrate‐community structure. We present a conceptual model that suggests that invertebrates in Great Lakes' marshes are distributed along gradients of decreased mixing of pelagic water and increases in sediment organic matter from outer to inner marsh and between littoral and adjacent inland marshes. Some invertebrates do best on one end of these gradients, while the majority are generalists found across habitat types.  相似文献   
162.
A major challenge for Indonesian economic policy makers is to avoid the recurrence of conditions that could trigger a new economic crisis. One of the important dimensions of this challenge will be to conduct fiscal policy in a way that is sustainable, given the level of interest rates and the rate of growth of the economy. This paper synthesises various approaches to the measurement of fiscal sustainability that have appeared in the economic literature, relates these measures to the fundamental concept of fiscal solvency, and applies the framework to Indonesia over the period 1991–2003. The domestic and foreign debt positions of the central government are treated separately, to capture the influence of exchange rate changes on the relative costs of domestic and foreign borrowing. The empirical analysis indicates that Indonesia has met the fiscal sustainability criterion in recent years, except when the rupiah has depreciated heavily.  相似文献   
163.
This paper uses a unique data set from 1957 to examine whether or not Blue Cross and Blue Shield suffered from an adverse selection death spiral after for-profit commercial insurance companies entered the market for health insurance. Results suggest that moving to experience rating may have helped the Blues counteract adverse selection in the group health insurance market. Adverse selection posed a greater problem for the Blues in the market for individual health insurance, possibly because of differences in the way the Blues screened potential enrollees relative to commercial insurance companies.  相似文献   
164.
This paper analyses the cost of capital of firms with foreign equity listings. Our purpose is to shed light on the question whether international and domestic asset pricing models yield a different estimate of the cost of capital for cross‐listed stocks. We distinguish between (i) the multifactor ICAPM of Solnik (1979) and Sercu (1980) including both the global market portfolio and exchange rate risk premia and (ii) the single factor domestic CAPM. We test for the significance of the cost of capital differential in a sample of 336 cross‐listed stocks from nine countries in the period 1980–99. Our hypothesis is that the cost of capital differential is substantial for firms with international listings, as these are often large multinationals with a strong international orientation. We find that the asset pricing models yield a significantly different estimate of the cost of capital for only 12% of the cross‐listed companies. The size of the cost of capital differential is around 50 basis points for the US, 80 basis points for the UK and 100 basis points for France.  相似文献   
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Using Turkish industry-level data from 1983 to 1990, we find that politically organized industries receive both higher protection and promotion than unorganized ones. Tariff rates are decreasing (increasing) in the import-penetration ratio and the absolute value of the import-demandelasticity for organized (unorganized) industries. Subsidy rates are decreasing (increasing) in the output-supply elasticity for organized (unorganized) industries. The results are consistent with the predictions of the Grossman–Helpman model and its extension in this paper. The mix of protection and promotion is inversely related to the ratio of their respective marginal deadweight cost measures.  相似文献   
167.
UNEMPLOYMENT, HYSTERESIS AND TRANSITION   总被引:3,自引:0,他引:3  
In this paper, we quantify the degree of persistence in the unemployment rates of transition countries using a variety of methods benchmarked against the EU. Initially, we work with the concept of linear ‘Hysteresis’ as described by the presence of unit roots in unemployment as in most empirical research on this area. Given that this is potentially a narrow definition, we also take into account the existence of structural breaks and nonlinear dynamics in unemployment. Finally, we examine whether CEECs' unemployment presents features of multiple equilibria, that is, if it remains locked into a new level whenever some structural change or sufficiently large shock occurs. Our findings show that, in general, we can reject the unit‐root hypothesis after controlling for structural changes and business‐cycle effects, but we can observe the presence of a high and low unemployment equilibria. The speed of adjustment is faster for CEECs than the EU, although CEECs tend to move more frequently between equilibria.  相似文献   
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