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331.
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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Lancaster  Thomas D. 《Publius》1997,27(4):115-134
Acknowledging Spain's diversity, this article assesses the impactof nationalism, regionalism, and other factors on public opinionabout the country's young democratic institutions. Utilizingsurvey data, the analysis focuses on national and regional variationsin public preferences for central state institutions and federalistor other designs for state-regional relations. It concludesthat a strong base of support exists for the current democraticsystem and the institutions through which it is implemented.Nevertheless, some doubts remain about the basic state structureof central-regional relations.  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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