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291.
The paper uses annual data from a panel of 334 Polish industrial enterprises over the period 1983–1988 to test empirically a simple neoclassical approach to the socialist labor market. First, an enterprise production function is estimated. The paper finds that for most enterprises, the resulting estimated marginal product of labor exceeds the wage paid by the enterprise by a considerable margin, suggesting general excess demand for labor. The paper then looks at how the difference between the MPL and the wage is related to the rate of change of employment, and finds that firms where the MPL is higher than the wage — firms which in a neoclassical model would have a large excess demand for labor — do not shed labor any more slowly than other firms. 相似文献
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Mark Attew 《The Modern law review》1995,58(5):696-701
It may also be presumed that contracts for the sale or other disposition of an interest in land (including leases) fall outside [the] provisions of [the Unfair Terms in Consumer Contracts Directive] (Chitty on Contracts, 27th ed, 1994, vol 1, at 14–091). 相似文献
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Mark H. Moore 《Journal of policy analysis and management》1983,2(2):185-195
Policy analysis has failed to guide gun control policy away from its current impasse because analysts have avoided facing several crucially important features of the current reality: the existence of some widely held values in the United States public that favor the possession of guns; the limitations on the ability of public agencies in the United States to enforce restraints on the possession of handguns; and the implications of the fact that so many guns are already in the hands of the public. These factors greatly reduce the possibility that effective measures will be introduced to reduce the existing supply of guns. Some effective measures of gun control may be possible nonetheless, mainly through the mobilization of large metropolitan police forces. 相似文献
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This paper exploits uniquely detailed data and cross-institution variation in aid for three large public universities to identify
the effects of aid on the probability of college graduation. The results indicate that need-based and merit-based aid both
increase graduation rates at large public institutions, but primarily through the types of students that ‘select’ these institutions.
Merit-based aid facilitates an institution attracting students who have higher observed academic ability that raises the probability
of graduation. Need-based aid enables an institution to attract students with non-academic attributes such as social and cultural
networks that, while often unobserved, improve graduation success. Broadly, our results suggest that recent aid policy that
has moved away from need-based aid for low-income students (reducing their ability to find the best institutional match) and
toward merit-based aid (that alters the distribution of high ability students across colleges) could foster stagnant graduation
rates even with rising enrollment rates that have been observed over the last three decades.
相似文献
Mark Stater (Corresponding author)Email: |
300.
In forensic evidence, gamma-hydroxybutyric acid (GHB) has frequently been encountered in one of its salt forms (gamma-hydroxybutyrate), but has also been encountered in its free acid form (GHB). Owing to the physical properties, encounters of the free acid have been largely restricted to forensic exhibits comprising aqueous solutions, such as acidic beverages that have been "spiked" or formulated with GHB salts or gamma-butyrolactone (GBL). The analysis of GHB free acid presents particular difficulties including the potential for altering the original proportions of GHB free acid, GHB carboxylate, and GBL in the course of analysis, and discrimination between GHB free acid and carboxylate forms. In this work, the formation of GHB free acid in aqueous solutions (water and/or D2O) was studied as a function of solution pH. Proton nuclear magnetic resonance (1HNMR) and Fourier-transform infrared spectrometry (FT-IR) measurements were obtained on freshly prepared mixtures of NaGHB and HCl stock solutions representing a series of points along the GHB titration curve. Both 1HNMR and FT-IR were shown to track the changing proportions of GHB free acid and carboxylate forms as a function of pH, while simultaneously monitoring for the formation of the lactone (GBL). The results were consistent with acid-base conversion behavior for a carboxylic acid. 1HNMR was shown to provide an ideal means for analysis of aqueous-based GHB/GBL forensic exhibits based on simple dilution of the neat liquid exhibit, without altering the original proportions of GHB free acid, carboxylate, and GBL in the samples. 相似文献