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排序方式: 共有10000条查询结果,搜索用时 406 毫秒
911.
To protect public-use microdata, one approach is not to allow users access to the microdata. Instead, users submit analyses to a remote computer that reports back basic output from the fitted model, such as coefficients and standard errors. To be most useful, this remote server also should provide some way for users to check the fit of their models, without disclosing actual data values. This paper discusses regression diagnostics for remote servers. The proposal is to release synthetic diagnostics—i.e. simulated values of residuals and dependent and independent variables–constructed to mimic the relationships among the real-data residuals and independent variables. Using simulations, it is shown that the proposed synthetic diagnostics can reveal model inadequacies without substantial increase in the risk of disclosures. This approach also can be used to develop remote server diagnostics for generalized linear models. 相似文献
912.
913.
James S. Jackson Ivy Forsythe-Brown Ishtar O. Govia 《The Journal of social issues》2007,63(4):729-743
Immigration is contributing to the U.S. population becoming increasingly ethnically diverse. This article examines the role of family relations and well-being among different generations of Black Caribbean immigrants. Family disruptions, such as migration, can have complex effects on the support networks and emotional well-being of family members. Data from a recently completed national study of American Blacks in the United States, however, reveal significant similarities across ancestry and immigrant status in family contact, solidarity and well-being. It is concluded that intrafamilial relations may serve to overcome barriers of geographical distance in providing comparable levels of contact, solidarity, and well-being for both U.S.-born and immigrant Black Caribbean family members of different generations. Because of the increasing numbers of immigrant elders, these sources of family support will become increasingly more important in bridging the gaps between government resources and needed assistance in an aging society. 相似文献
914.
张立光 《吉林师范大学学报》2003,(4):57-58
利用网络开展研究性学习具有很大的优势,探讨网络研究性学习能力的培养、组织与实施,以及网络研究性学习的评价对提高学生的综合素质有重要作用。 相似文献
915.
916.
Susan E. Frohlick 《Revue canadienne de sociologie》2003,40(5):525-542
Within the anthropology of tourism, “tourist” and “local” are often used to conceptualize social relations constitutive of international tourism, where “First World” mobile subjects visit stationary “Third World” “Others.” Globalization, as both discourse and condition, is changing the contours and conceptualizations of tourist spaces. In this paper, I show how “the global” is negotiated by different subjects, and how recreational mountain climbers from Nepal negotiate their identities as “locals” as well as global, mobile, travel subjects within “the global playscapes” of Himalayan mountaineering. I suggest that the question of who can be a tourist within a globalizing world should be closely examined. 相似文献
917.
Sets of alternatives as Condorcet winners 总被引:1,自引:0,他引:1
We characterize sets of alternatives which are Condorcet winners according to preferences over sets of alternatives, in terms
of properties defined on preferences over alternatives. We state our results under certain preference extension axioms which,
at any preference profile over alternatives, give the list of admissible preference profiles over sets of alternatives. It
turns out to be that requiring from a set to be a Condorcet winner at every admissible preference profile is too demanding,
even when the set of admissible preference profiles is fairly narrow. However, weakening this requirement to being a Condorcet
winner at some admissible preference profile opens the door to more permissive results and we characterize these sets by using
various versions of an undomination condition. Although our main results are given for a world where any two sets – whether
they are of the same cardinality or not – can be compared, the case for sets of equal cardinality is also considered.
Received: 15 March 2001/Accepted: 31 May 2002
This paper was written while Barış Kaymak was a graduate student in Economics at Boğazi?i University. We thank ?ağatay Kayı
and İpek ?zkal-Sanver who kindly agreed to be our initial listeners. The paper has been presented at the Economic Theory seminars
of Bilkent, Ko? and Sabancı Universities as well as at the Fifth Conference of the Society for the Advancement of Economic
Theory, July 2001, Ischia, Italy and at the 24th Bosphorus Workshop on Economic Design, August 2001, Bodrum, Turkey. We thank Fuad Aleskerov, İzak Atiyas, ?zgür Kıbrıs, Semih
Koray, Gilbert Laffond, Bezalel Peleg, Murat Sertel, Tayfun S?nmez, Utku ünver and all the participants. Remzi Sanver acknowledges
partial financial support from İstanbul Bilgi University and the Turkish Academy of Sciences and thanks Haluk Sanver and Serem
Ltd. for their continuous moral and financial support. Last but not the least, we thank Carmen Herrero and two anonymous referees.
Of course we are the sole responsible for all possible errors. 相似文献
918.
青少年疏离感的特点及其与家庭功能的关系 总被引:4,自引:0,他引:4
通过对875名初一至高二学生的问卷调查,探讨了青少年疏离感发展的特点及其与家庭功能的关系。结果发现:(1)青少年的环境疏离感最高,其次是社会疏离感,人际疏离感最低。(2)高中生疏离感显著高于初中生,在每一年龄段内,疏离感随年级升高而增强;但青少年疏离感性别差异不显著。(3)家庭功能中的角色、沟通、情感反应和情感介入可以显著正向预测青少年的疏离感,问题解决和行为控制对青少年疏离感的预测不显著。 相似文献
919.
To reduce nonresponse bias in sample surveys, a method of nonresponse weighting adjustment is often used which consists of multiplying the sampling weight of the respondent by the inverse of the estimated response probability. The authors examine the asymptotic properties of this estimator. They prove that it is generally more efficient than an estimator which uses the true response probability, provided that the parameters which govern this probability are estimated by maximum likelihood. The authors discuss variance estimation methods that account for the effect of using the estimated response probability; they compare their performances in a small simulation study. They also discuss extensions to the regression estimator. 相似文献
920.
碎屑岩储层孔隙演化受有机-无机成岩作用的影响,在埋藏成岩阶段,有机质成熟过程中脱羧作用产生的有机酸对碎屑岩中的方解石、长石等溶蚀所形成的次生扎隙,是深部储层中高孔渗段发育的重要原因,随埋深增加,成岩阶段由早-晚发展,有机质由未成熟-成熟演化,在此期间,储层孔隙经历了消亡与新生的发展过程。在同一盆地中,不同层位储层经历的最大埋深如果相近,所处成岩阶段也相近,其孔隙演化史亦趋于相似;反之,同一层位的储层所处的最大埋深不同,成岩阶段不同,其孔隙特征也就不同。 相似文献