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91.
In this article, we first propose the modified Hannan–Rissanen Method for estimating the parameters of autoregressive moving average (ARMA) process with symmetric stable noise and symmetric stable generalized autoregressive conditional heteroskedastic (GARCH) noise. Next, we propose the modified empirical characteristic function method for the estimation of GARCH parameters with symmetric stable noise. Further, we show the efficiency, accuracy and simplicity of our methods with Monte-Carlo simulation. Finally, we apply our proposed methods to model the financial data.  相似文献   
92.
Two-year chronic bioassays were conducted by using B6C3F1 female mice fed several concentrations of two different mixtures of coal tars from manufactured gas waste sites or benzo(a)pyrene (BaP). The purpose of the study was to obtain estimates of cancer potency of coal tar mixtures, by using conventional regulatory methods, for use in manufactured gas waste site remediation. A secondary purpose was to investigate the validity of using the concentration of a single potent carcinogen, in this case benzo(a)pyrene, to estimate the relative risk for a coal tar mixture. The study has shown that BaP dominates the cancer risk when its concentration is greater than 6,300 ppm in the coal tar mixture. In this case the most sensitive tissue site is the forestomach. Using low-dose linear extrapolation, the lifetime cancer risk for humans is estimated to be: Risk < 1.03 x 10(-4) (ppm coal tar in total diet) + 240 x 10(-4) (ppm BaP in total diet), based on forestomach tumors. If the BaP concentration in the coal tar mixture is less than 6,300 ppm, the more likely case, then lung tumors provide the largest estimated upper limit of risk, Risk < 2.55 x 10(-4) (ppm coal tar in total diet), with no contribution of BaP to lung tumors. The upper limit of the cancer potency (slope factor) for lifetime oral exposure to benzo(a)pyrene is 1.2 x 10(-3) per microgram per kg body weight per day from this Good Laboratory Practice (GLP) study compared with the current value of 7.3 x 10(-3) per microgram per kg body weight per day listed in the U.S. EPA Integrated Risk Information System.  相似文献   
93.
This paper investigates how workers’ “economic struggle” determines the “democratic class struggle,” and extends socialist electoral constituency. This paper argues that political outcomes, namely, electoral behavior, may not be understood independently of the labor process, especially its most militant manifestation, strikes. Rather than follow the customary conceptual dichotomy between the sphere of production and the political sphere, it is suggested that both strike activity and electoral participation are compatible political strategies that, under specific historical circumstances, may jointly determine the fate of the Socialist party. The leading question is how did the wave of strikes in post World War I Italy affect the electoral power of the Italian Socialist party, in comparison with another mass party, the Popular Catholic Party. Hierarchical Linear Modeling (HLM) is employed to analyze census, strike, and electoral data. It is found that strike activity and electoral democracy increased the electoral power of the Socialist party, whereas they had little effect on the power of the Catholic party. It is suggested that this was due to the Catholic non-revolutionary program which was ambivalent about the political role of strikes. It is concluded that the socialists’ political success was determined by their dual political strategy in both spheres, electoral participation, and organizing strikes.  相似文献   
94.
95.
The purpose of this paper is firstly to investigate the distribution of two parent low income families in England and Wales and Scotland for see to what extent they differ, and secondly to examine the relative importance of certain contributing factors in determining the distributions. From an analysis of Family Expenditure Survey data it is found that although it is difficult to arrive at statistically verifiable conclusions about the nature of the distributions, interesting qualitative observations can be made.  相似文献   
96.
This paper is designed to bring into focus the numerous modeling attempts to analyze commodity price stabilization that have recently appeared. The studies examined begin with the Waugh-Oi-Massell framework and advance to econometric commodity modeling. Such a critique is considered necessary: None of the studies examined has overcome the myriad of problems that analysts have pointed out as essential for assessing the welfare outcomes of price stabilization schemes. As a consequence, stabilization analyses for similar commodities have produced conflicting results regarding predicted welfare outcome. The present appraisal attempts to provide a unity of direction to this work by (1) comparing recieved studies of a theoretical, empirical, and econometric modeling nature, and (2) suggesting possibilities for improving modeling analyses.  相似文献   
97.
This study is based on repeated interviews with twelve heterosexual female commercial sex workers (SWs) in Perth. These informants deploy, with various degrees of success, strategies to demarcate ‘work-sex’, with its socially ascribed stigma, from ‘non-work sex’. Such strategies inhibit the spread of HIV at work but, ironically, increase the risk of HIV transmission during non-work sex. SWs recognise this risk and construct a variety of rationales to reduce their fear of contracting HIV and justify their strategies of demarcating work-sex from non-work sex. Efforts to reduce the risk of HIV infection among Perth SWs would seem to depend upon addressing not only these strategies of demarcation but these rationales in a supportive environment that recognises the creative complexities of their lives.  相似文献   
98.
99.
Objectives . Property rights are central to debates about natural resource policy. Governments traditionally have been seen as the appropriate custodians of natural resources for their citizens. More recently, many argue the privatization of property rights will ensure that users have incentives to manage their resources well. Common property, to the extent it is discussed at all, is seen as leading to the tragedy of the commons. We evaluate these claims by assessing property rights and forest conditions in two private and three communal forests in Guatemala. Methods . Data on biological and social phenomena from five forests (151 plots) and their associated communities were collected using the International Forestry Resources and Institutions Research Program protocols. Ordinary least squares regression was used to analyze four models. We examined t -scores for differences in coefficients for the different models. Results . The models demonstrate that de jure property rights are not a powerful predictor of variations among the sampled forests. Conclusions . We argue that de facto institutions and their enforcement are much more important than de jure property rights to forest management. Communities holding a forest in common can, under certain circumstances, create institutions to manage their resources as successfully as—or more successfully than—private owners.  相似文献   
100.
Hearing the voices of abused older women   总被引:1,自引:0,他引:1  
This paper focuses on a qualitative research process that gathered responses from 64 older women aged fifty and older on their experience of violence and abuse. What older women said about abuse in their lives supports the use of a feminist framework as well as the age based analysis of the elder abuse field. Some respondents spoke of abuse from childhood into their later years. Some spoke of partners witnessing or experiencing abuse as children. Some women express concern about possible abuse by their adult children of their own children. Abused older women like younger women need a safe environment, emotional support, advocacy, information, and peer support. While it is important to consider the perspectives and knowledge of service providers when developing policy and practice on abuse of older women, it is critical to ask the women survivors of abuse or neglect what they believe would benefit them, and others in similar situations.  相似文献   
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