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21.
随着网络经济时代的到来, 人们通过缔结电子合同来进行交易的情况越来越多。由于电子合同存在种种难以预测的特殊风险, 故而需要对其加以法律控制, 而公证作为国家法律证明手段, 若应用到电子合同中, 势必能降低电子合同的特殊风险。  相似文献   
22.
关于"体育社会问题"的辨析   总被引:1,自引:0,他引:1  
体育社会学作为一门新兴的学科,已日趋成熟.其主要内容之一,是研究和解决体育社会问题,然而什么是体育社会问题,目前理论界尚无定论.该通过分析,指出了体育社会问题的两重属性:通性——危害社会秩序;特性——影响体育发展.同时尝试给出体育社会问题的定义,以供参考讨论.  相似文献   
23.
探讨了学校体育在我国体育建设中的战略地位 ,并结合实际分析了我国体育战略布局的现状 ,旨在为当前的体育教学改革理清思路以便及时发现改革中出现的问题  相似文献   
24.
The L1 and L2-errors of the histogram estimate of a density f from a sample X1,X2,…,Xn using a cubic partition are shown to be asymptotically normal without any unnecessary conditions imposed on the density f. The asymptotic variances are shown to depend on f only through the corresponding norm of f. From this follows the asymptotic null distribution of a goodness-of-fit test based on the total variation distance, introduced by Györfi and van der Meulen (1991). This note uses the idea of partial inversion for obtaining characteristic functions of conditional distributions, which goes back at least to Bartlett (1938).  相似文献   
25.
Generalized partially linear varying-coefficient models   总被引:1,自引:0,他引:1  
Generalized varying-coefficient models are useful extensions of generalized linear models. They arise naturally when investigating how regression coefficients change over different groups characterized by certain covariates such as age. In this paper, we extend these models to generalized partially linear varying-coefficient models, in which some coefficients are constants and the others are functions of certain covariates. Procedures for estimating the linear and non-parametric parts are developed and their associated statistical properties are studied. The methods proposed are illustrated using some simulations and real data analysis.  相似文献   
26.
研究了碳源、氮源、无机盐、金属离子等培养基组成和初始pH、通风量、温度等发酵条件对短杆菌(Bre vibacteriumspWX 10)产酶的影响,通过正校试验优化得到的产酶培养基组成及发酵条件:蔗糖1%,NaCl2 5%,牛肉膏0 05%,NaNO30 05%,pH7 5,500mL三角瓶装培养基50mL,30℃于220r/min旋转式摇床上培养72h.在该培养条件下WX 10产酶量是原培养条件下的1 85倍.  相似文献   
27.
There are many models that require the estimation of a set of ordered parameters. For example, multivariate analysis of variance often is formulated as testing for the equality of the parameters versus an ordered alternative. This problem, referred to as isotonic inference, constrained inference, or isotonic regression, has led to the development of general solutions, not often easy to apply in special models. In this expository paper, we study the special case of a separable convex quadratic programming problem for which the optimality conditions lead to a readily solved linear complementarity problem in the Lagrange multipliers, and subsequently to an equivalent linear programming problem, whose solution can be used to recover the solution of the original isotonic problem. The method can be applied to estimating ordered correlations, ordered binomial probabilities, ordered Poisson parameters, ordered exponential scale parameters, or ordered risk differences.  相似文献   
28.
In order to assess the effectiveness of government programs designed to reduce disparities in the health care minority groups receive relative to the majority white population, a proper statistical measure should be used. This article proposes a measure of and its accompanying graph, which is readily interpretable and is not affected by the number of minority subgroups examined.  相似文献   
29.
The basic assumption underlying the concept of ranked set sampling is that actual measurement of units is expensive, whereas ranking is cheap. This may not be true in reality in certain cases where ranking may be moderately expensive. In such situations, based on total cost considerations, k-tuple ranked set sampling is known to be a viable alternative, where one selects k units (instead of one) from each ranked set. In this article, we consider estimation of the distribution function based on k-tuple ranked set samples when the cost of selecting and ranking units is not ignorable. We investigate estimation both in the balanced and unbalanced data case. Properties of the estimation procedure in the presence of ranking error are also investigated. Results of simulation studies as well as an application to a real data set are presented to illustrate some of the theoretical findings.  相似文献   
30.
In this paper we propose a new nonparametric estimator of the conditional distribution function under a semiparametric censorship model. We establish an asymptotic representation of the estimator as a sum of iid random variables, balanced by some kernel weights. This representation is used for obtaining large sample results such as the rate of uniform convergence of the estimator, or its limit distributional law. We prove that the new estimator outperforms the conditional Kaplan–Meier estimator for censored data, in the sense that it exhibits lower asymptotic variance. Illustration through real data analysis is provided.  相似文献   
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