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71.
Hidetoshi Matsui 《统计学通讯:模拟与计算》2019,48(6):1784-1797
Sparsity-inducing penalties are useful tools for variable selection and are also effective for regression problems where the data are functions. We consider the problem of selecting not only variables but also decision boundaries in multiclass logistic regression models for functional data, using sparse regularization. The parameters of the functional logistic regression model are estimated in the framework of the penalized likelihood method with the sparse group lasso-type penalty, and then tuning parameters for the model are selected using the model selection criterion. The effectiveness of the proposed method is investigated through simulation studies and the analysis of a gene expression data set. 相似文献
72.
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
73.
徐孝明 《湛江师范学院学报》2012,33(1):106-110
20世纪70年代的国际石油危机有着深厚的历史根源,它源于国际石油权力结构的急剧变革。60年代后期开始,随着国际石油市场日趋紧张,产油国的地位日益改善,它们从石油公司获得越来越多的石油权力,其中国际石油公司与产油国签订的"德黑兰协定"和"的黎波里协定"发挥了至关重要的作用,是产油国能够针对西方国家使用减产、禁运和提价等石油武器的前提条件。 相似文献
74.
What can we learn from twin studies? A comprehensive evaluation of the equal environments assumption
Twin studies are a major source of information about genetic effects on behavior, but they depend on a controversial assumption known as the equal environments assumption (EEA): that similarity in co-twins’ environments is not predictive of similarity in co-twin outcomes. Although evidence has largely supported the EEA, critics have claimed that environmental similarity has not been measured well, and most studies of the EEA have focused on outcomes related to health and psychology. This article addresses these limitations through (1) a reanalysis of data from the most cited study of the EEA, Loehlin and Nichols (1976), using better measures, and through (2) an analysis of nationally representative twin data from MIDUS using more comprehensive controls on a wider variety of outcomes than previous studies. Results support a middle ground position; it is likely that the EEA is not strictly valid for most outcomes, but the resulting bias is likely modest. 相似文献
75.
The main aim of this study is to investigate India's demand for international reserve by focusing on the role of national monetary disequilibrium and to present new benchmarks for assessing the adequacy of international reserves. We assessed India's position in terms of reserve adequacy and found that India is well placed and has sufficient stock of international reserves to meet the minimum adequacy requirements. Also, the results reveal that the central bank is holding substantial excess reserves and the related opportunity cost (1.5% of GDP) appears to be quite considerable. Further, the estimates of reserve demand function suggest that scale of foreign trade, uncertainty and profitability considerations play significant role in determining India's long-term reserve demand policies. More importantly, validating the monetary approach to balance of payment, our results show that national monetary disequilibrium does play a crucial role in short-run reserve movements. An excess of money demand (supply) induces an inflow (outflow) of international reserves with an elasticity of 0.56 which also implies that Reserve Bank of India responds to correct the domestic money market disequilibrium; and did not just leave it completely on the mercy of reserve inflows. 相似文献
76.
In this paper, we demonstrate how public opinion surveys can be designed to collect information pertinent to computational behavior modeling, and we present the results of a public opinion and behavior survey conducted during the 2009–2010 H1N1 influenza pandemic. The results are used to parameterize the Health Belief Model of individual health‐protective decision making. Survey subjects were asked questions about their perceptions of the then‐circulating influenza and attitudes towards two personal protective behaviors: vaccination and avoidance of crowds. We empirically address two important issues in applying the Health Belief Model of behavior to computational infectious disease simulation: (1) the factors dynamically influencing the states of the Health Belief Model variables and (2) the appropriateness of the Health Belief Model in describing self‐protective behavior in the context of pandemic influenza. 相似文献
77.
78.
To enhance modeling flexibility, the authors propose a nonparametric hazard regression model, for which the ordinary and weighted least squares estimation and inference procedures are studied. The proposed model does not assume any parametric specifications on the covariate effects, which is suitable for exploring the nonlinear interactions between covariates, time and some exposure variable. The authors propose the local ordinary and weighted least squares estimators for the varying‐coefficient functions and establish the corresponding asymptotic normality properties. Simulation studies are conducted to empirically examine the finite‐sample performance of the new methods, and a real data example from a recent breast cancer study is used as an illustration. The Canadian Journal of Statistics 37: 659–674; 2009 © 2009 Statistical Society of Canada 相似文献
79.
我国大规模区域建设必须举国家之力,靠体制优势;我国区域发展布局不能非此即彼,要走协调发展之路;我国西部落后区域的发展要依靠其比较优势的发挥;改善区域布局是我国现代化进程中长期、艰巨的任务;我国区域发展应力求使国防安全原则与区域经济建设规律有机统一起来。 相似文献
80.
独立董事制度产生后对美国公司治理起到了很大作用,并在其他国家迅速推广发展。该制度的引入本是我国上市公司解决内部人控制、一股独大问题的有利契机,但由于各种原因,独立董事在上市公司大股东侵害中小股东利益时未能发挥其应有的效用。文章通过对比研究我国与英美国家在独立董事功能定位、职权和责任上的不同之处,对完善我国独立董事机制提出一些建议。 相似文献