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1.
We give an example of a subspace K of     such that     , where     denotes the closure with respect to convergence in probablity. On the other hand, the cone   C ≔ K − L +  is dense in   L   with respect to the weak-star topology  σ( L , L 1)  . This example answers a question raised by I. Evstigneev. The topic is motivated by the relation of the notion of no arbitrage and the existence of martingale measures in Mathematical Finance.  相似文献   
2.
In this study, we measured growth trends in oxygen and carbon isotopic ratios in whole sagittal otoliths from three adult centropomid fish (Lates stappersii) from each of three sub-basins of Lake Tanganyika, East Africa. Sampling density was 20 to 50 samples per otolith. Both δ18O and δ13C values increase with age. The δ18O data suggest that otoliths were precipitated near the expected equilibrium with the ambient environment (ca. +3.5‰) and support a migration pattern from surface waters during larval stages to deeper waters (40 to 80 m) for mature fish. Relatively high δ18O values in the southern sub-basin are consistent with cooler temperatures in the region during seasonal upwelling. The δ13C increase from otolith core to edge is large (up to 4‰) and is interpreted as due to ontogenetic changes in diet and contributions from a decrease in the proportion of respired CO2 incorporated into otolith carbonate as metabolic rates of the fish dropped with maturity. The data seem to successfully reveal life strategy and migration patterns of L. stappersii, document regional differences in lake conditions, and provide a record of temperature within the water column during which the fish lived. Higher resolution studies and analyses of historical samples could be used to constrain modern and past growth patterns, and to reconstruct past temperature gradients and productivity patterns in the lake.  相似文献   
3.
This paper is focused on the cost of raising capital in Germany. A cross-sectional analysis of flotation cost data for 117 IPOs over the years 1993–1998 is presented. We find average flotation costs to be 7.77 percent of gross proceeds, while underwriting fees average 5.01 percent. Our results extend the literature in two important directions. First, contrary to the conventional economies of scale view we find marginal spreads to be rather constant in gross proceeds and to be higher for more risky and more complex offerings. Fixed costs amount to 5 to 9 percent of underwriting fees. Second, by applying a principal component analysis we find issue size, an issuer risk factor, and an offering method complexity factor to have an economicaly meaningful impact on underwriting fees.  相似文献   
4.
The model of public policy studied in this paper has heterogeneous citizens/voters and two public goods: one (roads) chosen directly by an elected policy‐maker, and the other (pollution) stochastically dependent on the amount of roads. Both a one‐country and a two‐country version of the model are analyzed; the latter displays externalities across the countries which create incentives for free riding and strategic delegation. The welfare effects of providing the policy‐maker with information about the relationship between roads and pollution are investigated, and it is shown that more information hurts some—sometimes even all—citizens. In particular, the opportunity not to create an institution for information gathering can serve as a commitment device for a country, although with the unfortunate effect of making the overall outcome even worse. Implications for the welfare effects of “informational lobbying” are also discussed.  相似文献   
5.
Based on a contingent perspective of accounting change, this paper reviews the historical development of differential reporting in Germany, by drawing on primary and secondary sources. The main objective of the paper is to shed light on the driving forces and main influential parameters that have shaped the existing differential reporting framework. This historical approach supplies interesting insights for the current discussion on differential reporting in Germany produced by the EU Regulation on the application of International Accounting Standards.  相似文献   
6.
The comparison of true cost of living indices between demographically different households (relative equivalence scale) is argued to be sensitive to the way demographic characteristics enter demand analysis. In particular, parameters reflecting the cost of demographic characteristics at base prices, though themselves do not have welfare (equivalence scale) interpretation, can alter the benchmark from which demographically varying inflation effects are measured. The empirical analysis, based on a rank‐3 demand system applied to UK individual household data, shows that the inflation adjustment of child benefits can vary with the way demographic costs at base period prices are specified.  相似文献   
7.
唐代的法制思想,主要有两大特征,即仁刑恤典和厉行法制。对此,学者们多从正史的角度加以探讨和分析。而从敦煌所出唐代蒙书《百行章》所述内容同样清楚地显示了唐初的法制思想的以上特点。这一研究可以起到补充正史的作用。  相似文献   
8.
Underdetermination, associated with the Duhem–Quine thesis,is a familiar if under-researched theme in economics. In thelight of this, we examine the development of urban land andhousing economics. Through its Cartesian dualistic delineationof theory and data, the contemporary mainstream approach appearsunable to circumvent the problem of underdetermination. In effect,it employs the strong version of Duhem–Quine in its retentionof the assumption of a single, unitary competitive market (andassociated access–space trade-off). Conversely, we highlightthe affinity of Ely's (and the later Columbia School's) approachto pragmatists Dewey and Peirce, which provides a more fruitfulbasis for explanation.  相似文献   
9.
In his 1960 book, Sraffa suggested using a composite commodity,which he called the ‘Standard commodity’, to solveRicardo's search for an invariable measure of value, i.e., astandard capable of isolating the price movements of any othercommodity induced by changes in income distribution. The absencein Sraffa's book of an explicit proof of the invariance propertyof this standard gave rise to many misunderstandings about itsmeaning and its role as an invariable measure of value. In orderto clear up these questions, Bellino (On Sraffa's Standard commodity,Cambridge Journal of Economics, vol. 28, 121–32, 2004)has proposed a ‘proper’ definition of an ‘invariablemeasure of value’, showing that Sraffa's Standard commoditydoes fulfil the requirements of this definition. He claims thatthe fulfilment of this property (but not the constancy of its‘nominal’ price) qualifies the Standard commodityas an invariable measure of value. In this paper, a proof ofthe invariance of the price of the Standard commodity with respectto changes in income distribution is given, and the equivalenceof this property with Bellino's definition of invariance isshown.  相似文献   
10.
龙潭拱坝坝高90m,砼上坝运输是砼施工过程中的中间环节,控制进度的关键,必须因时因地制宜地选择适当的运输机械和运输方案,使砼运输能做到保质、保量、及时和经济,通过论证比较,结合本工程现实情况,砼上坝运输不采用缆机而采用门机方案.  相似文献   
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