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1.
近代以来,国内学者一直探讨美国的“毒树之果”理论,讨论我国是否应该建立非法证据的排除规则。在近代的联邦德国,也有证据排除理论,名为“证据禁止”理论,它与美国的毒树之果理论相比,更加注重在司法实践中的应用。探讨联邦德国禁止使用的证据是否有“远距离的影响”,即德国的“毒树之果”是否应当排除其证明力,以期找到该理论对中国的启示。  相似文献   
2.
The Web proxy location problem in general networks is an NP-hard problem. In this paper, we study the problem in networks showing a general tree of rings topology. We improve the results of the tree case in literature and get an exact algorithm with time complexity O(nhk), where n is the number of nodes in the tree, h is the height of the tree (the server is in the root of the tree), and k is the number of web proxies to be placed in the net. For the case of networks with a general tree of rings topology we present an exact algorithm with O(kn 2) time complexity.This research has been supported by NSF of China (No. 10371028) and the Educational Department grant of Zhejiang Province (No. 20030622).  相似文献   
3.
The restricted minimum φ-divergence estimator, [Pardo, J.A., Pardo, L. and Zografos, K., 2002, Minimum φ-divergence estimators with constraints in multinomial populations. Journal of Statistical Planning and Inference, 104, 221–237], is employed to obtain estimates of the cell frequencies of an I×I contingency table under hypotheses of symmetry, marginal homogeneity or quasi-symmetry. The associated φ-divergence statistics are distributed asymptotically as chi-squared distributions under the null hypothesis. The new estimators and test statistics contain, as particular cases, the classical estimators and test statistics previously presented in the literature for the cited problems. A simulation study is presented, for the symmetry problem, to choose the best function φ2 for estimation and the best function φ1 for testing.  相似文献   
4.
We investigated two aspects of credit card repayment decisions: the extent to which the anchoring effect of minimum repayment information may be mitigated by information on alternative anchors, specifically repayments that would repay the balance in two years (Study 1) or nine months (Study 2); and the role of future repayment concern. In two experiments, three realistic credit card statements were presented with different outstanding balances. Participants, who were randomly allocated to one of four information conditions depending on supplementary information provided on the statements, stated how much they would repay that month. They were then asked about concerns they would have about repayment difficulties if they had a fixed consumer loan over three years. In Study 1 the alternative two-year repayment anchor had a negative effect on percent repayment, whereas in Study 2 the nine-month repayment anchor had a significant positive effect, especially for those with higher future repayment concern. Also, in both studies, future repayment concern had a direct inverse effect on repayment decisions which partially mediated the effect of disposable income. It is concluded that the addition to credit card statements of a table of cost and duration information for a range of repayment amounts may usefully support repayment decisions.  相似文献   
5.
股利分配政策是上市公司对盈利进行分配或留存的决策问题.在大数据时代运用微软商业智能中的决策树算法,可以对农业上市公司的相关财务数据进行深入挖掘.通过决策树规则进行分析,找出农业上市公司股利分配采购影响因素,为农业上市公司制定现金股利分配股利分配政策提供决策依据,也为商业智能工具在企业决策中的运用提供借鉴.  相似文献   
6.
《绿化树》与《男人的一半是女人》,以人性最基本的构成部分食、性为透视角度,对主人公知识分子章永璘在苦难、饥馑的压迫下与非人的政治炼狱中,在本能驱动下真实的灵魂波动及人性堕落、精神毁损的悲剧进行了细致剖析。在“落难”这一特殊的生命情境中,“洛神”式的人物马缨花、黄香久对他进行了灵与肉的双重拯救,可知识分子的文化优越感和精神本能,又使他在重获新生后,必然会背叛他的“洛神”,去追求更高远的境界。这有关“拯救”与“背叛”的“阴暗记忆”,再现了时代重轭之下一代人的命运图景,勾勒了中国当代“落难精英”的历史剪影。  相似文献   
7.
Statistical inference procedures based on transforms such as characteristic function and probability generating function have been examined by many researchers because they are much simpler than probability density functions. Here, a probability generating function based Jeffrey's divergence measure is proposed for parameter estimation and goodness-of-fit test. Being a member of the M-estimators, the proposed estimator is consistent. Also, the proposed goodness-of-fit test has good statistical power. The proposed divergence measure shows improved performance over existing probability generating function based measures. Real data examples are given to illustrate the proposed parameter estimation method and goodness-of-fit test.  相似文献   
8.
将教育资本分解成受教育程度和职业的各种组合,借鉴Markowiz的有效投资组合理论,计算Mincer收入方程中扰动项的均值—标准差来衡量投资风险收益,以此建立中国教育投资风险和收益之间的平衡关系,并且利用F检验衡量投资组合的均值方差张成。结果表明,有效的教育资本组合不仅与所接受教育程度有关,还与未来职业选择有关。在以受教育程度为高中和中等职业的基础上,高中(06)可以张成其他全部14个投资组合的均值方差边界。因此,个体和政府在进行教育投资时,都需要全面衡量投资组合的风险收益平衡问题。  相似文献   
9.
<圣女贞德传>表面上是一部圣女贞德的传记,实际上是小说中的叙述者德·孔泰的心灵成长史.整部小说的情节按照天真--神启(诱惑)与出走--冒险--迷惘--顿悟的顺序展开.文中的仙女树,象征着成长的意义和作者的自然神崇拜,它是作者与德*孔泰共同的精神家园.  相似文献   
10.
Randomized response techniques are widely employed in surveys dealing with sensitive questions to ensure interviewee anonymity and reduce nonrespondents rates and biased responses. Since Warner’s (J Am Stat Assoc 60:63–69, 1965) pioneering work, many ingenious devices have been suggested to increase respondent’s privacy protection and to better estimate the proportion of people, π A , bearing a sensitive attribute. In spite of the massive use of auxiliary information in the estimation of non-sensitive parameters, very few attempts have been made to improve randomization strategy performance when auxiliary variables are available. Moving from Zaizai’s (Model Assist Stat Appl 1:125–130, 2006) recent work, in this paper we provide a class of estimators for π A , for a generic randomization scheme, when the mean of a supplementary non-sensitive variable is known. The minimum attainable variance bound of the class is obtained and the best estimator is also identified. We prove that the best estimator acts as a regression-type estimator which is at least as efficient as the corresponding estimator evaluated without allowing for the auxiliary variable. The general results are then applied to Warner and Simmons’ model.  相似文献   
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