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51.
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   
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The Tax Reform Act of 1986 rewrote the federal income tax code, bringing it closer to policy professionals' vision of what constitutes an equitable and efficient income tax. Research on tax compliance suggests the law might have affected taxpayer compliance in three ways: by reducing opportunities to overstate deductions, by changing perceptions of fairness, and by altering tax liabilities. Changes in taxpayer perceptions, attitudes, and noncompliance intentions were examined in three bodies of survey data, each containing pre-and post-reform data from independent samples of the same population. The results show an improved normative climate for taxpayer compliance and point to both the feasibility and the importance of examining the effects of substantive tax policies on taxpayer perceptions, attitudes, and behavioral intentions.  相似文献   
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The formation of adequate mental health systems within prisons has accelerated as a result of successful class action lawsuits. Our recent national survey questioned all state correctional departments about the existence of standards in each system, compliance with such standards, prevalence of class action lawsuits involving the issue of providing adequate mental health services for inmates, issues related to consent decrees, available mental health resources within the correctional system, and the administrative structure of the mental health system. Our purpose was to identify those factors correlated with certified class action lawsuits involving issues related to mental health services. Twenty-one states were involved in such litigation. Only the presence of psychiatric hospitals operated by the department of corrections correlated with the presence of certified class action lawsuits involving mental health services. Prison systems larger than 15,000 inmates were at higher risk for such litigation. Smaller systems having psychiatric hospitals run by the state mental health agency appeared to be at less risk for such litigation.  相似文献   
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Bone fragments were stored in water for 2 years at room temperature and investigated serologically using the following methods: Absorption-elution, extraction of blood group substances and immunohistochemistry (PAP). All 3 methods gave essentially specific results for fresh bone tissue but with putrid bone tissue unspecific reactions were found predominantly with the absorption-elution and PAP techniques. In contrast, more specific reactions were obtained from the extracts although they were much weaker. From this it can be concluded that pure physical binding plays a substantial role in the unspecific reaction between antibodies and bone material. It is suggested that the relevant physical properties are altered by putrification.  相似文献   
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This paper addresses two neglected areas in the research on the relationship between family violence and violence outside the home: violence other than parent-child abuse and the effect of gender. Specifically, we consider both parental and sibling violence as independent variables, nonfamily violence as the dependent variable, and gender as the specification variable. The data were collected from a sample of 306 students in Introductory Sociology and Social Problems classes. The finding of particular importance is that the interaction between the gender of both the aggressor and the victim has a significant effect on the relationship between violence within the home and nonfamily violence.  相似文献   
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The Green River Murder Investigation in King County, Washington, is currently the longest active serial murder investigation in U.S. history. During its course, over 26 separate scenes with from one to five victims each have been processed. The experience of the authors is presented in order to acquaint other agencies with techniques of outdoor scene processing that have evolved during recovery of remains from Green River and other skeletal cases.  相似文献   
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