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41.
Rebecca Emerson Stephen G. Hall Anna Zalewska-Mitura 《Economic Change and Restructuring》1997,30(2-3):75-90
With new technically advanced methods and computers at our disposal, the efficient market hypothesis is once again being debated. At the same time, we are witnessing an unprecedented growth in both existing and new financial markets. These new markets are often in economies which have just recently embraced free market economics; we term these stock markets infant markets. Such stock markets are obviously not efficient in allocating the supply of savings to productive capital. We do not test whether or not these infant markets are informationally efficient, but instead examine whether and how they are becoming more efficient. We propose modelling the excess returns of individual securities using a multi-factor model with time-varying coefficients and generalised auto-regressive conditional heteroskedastic (GARCH) errors. If the markets are becoming more informationally efficient or the agents are learning, we would expect this to manifest itself as the time-varying coefficients becoming more stable as time increases. We test our model using data on four Bulgarian shares. First, we estimate an AR(2) model and a GARCH-M(1,1) model for the shares. Then, we estimated our AR(2) model with time varying coefficients and GARCH type errors. We find varying levels of efficiency and varying speeds of movement towards efficiency within our sample of four shares. 相似文献
42.
Correlation between plasma and bone marrow tricyclic antidepressants has not been studied before. Two groups of rabbits were given 10 and 20 mg of desipramine/kg body weight, respectively. Desipramine was administered to the animals once daily by mouth for 5 days. On the fifth day the animals were sacrificed and blood and bone marrow samples were collected and analyzed using a high performance liquid chromatographic (HPLC) method. Data showed that a correlation exists between bone marrow and blood desipramine. The bone marrow desipramine concentration increased as its blood levels increased. The average ratio of bone marrow to blood desipramine +/- S.D. (standard deviation) in both dosage groups was 37.2 +/- 4.46 with a range of 30.99-44.82. This investigation is promising and shows that bone marrow could be used as an alternative tissue in the absence of a suitable blood sample. 相似文献
43.
Carol S. Bruch 《Family Court Review》1993,31(1):101-107
This article examines voluntary mediation and provides suggested criteria for attorneys in deciding whether or not to use mediation. The author discusses what mediation has to offer, what it takes to make it work, and important cautions for attorneys in deciding about the use of this process. 相似文献
44.
Identification of the driver in two-rider motorcycle accidents. Inguinal contusion-laceration as an indication of the driver 总被引:1,自引:0,他引:1
H Shiono A Akane K Matsubara K Tanabe S Takahashi 《The American journal of forensic medicine and pathology》1990,11(3):190-192
In motorcycle accidents involving two riders, medicolegal identification of the driver is necessary when one or both riders die. It is particularly important in the latter case, because the survivor almost always insists that he or she was not driving. One characteristic injury that distinguishes the driver from the passenger is inguinal contusion-laceration (accompanied internally by pelvic fracture). This injury, caused by collision of the pelvis with the fuel tank, identifies the driver. 相似文献
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46.
Jill S. Cannon Alison Jacknowitz Gary Painter 《Journal of policy analysis and management》2006,25(2):299-321
Kindergarten policy varies widely both across and within states. Over the past decade, a number of states have instituted a full‐day kindergarten requirement and others are considering it as a way to increase educational achievement. Many parents also support full‐day kindergarten as a source of child care. This paper uses the Early Child Longitudinal Study–Kindergarten Class of 1998–1999 to evaluate the efficacy of this policy. In ordinary least squares, probit, county fixed effects, and instrumental variables models, we find that there are initial benefits for students and the mothers of students who attend full‐day kindergarten, but that these differences largely evaporate by third grade. Contrary to claims by some advocates, attending full‐day kindergarten is found to have no additional benefit for students in families with income below the poverty threshold. © 2006 by the Association for Public Policy Analysis and Management 相似文献
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In the statistical interpretation of forensic glass evidence it is standard practice to make the assumption of homogeneity of the refractive index (RI) of the source glass, or of localized homogeneity. However, the work of Locke and Hayes showed that, for toughened windscreen glass, this assumption might not be true. This work is well cited, but there appears to have been little follow-on published research. Furthermore, the toughening process is something known to affect the refractive index, and is a process that float glass does not undergo. Float glass is a major component of casework in New Zealand and for that reason it would be interesting to know whether the findings of Locke and Hayes apply when dealing with float glass. In this paper we describe an experiment similar to that of Locke and Hayes, systematically examining the variation of RI in a pane of float window glass. It was found that, although there were no systematic differences in refractive index, there were observable differences across the pane. 相似文献