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1.
Previously, a method was proposed for calculating a reconstructed coefficient of determination in the case of right-censored regression using the expectation–maximization (EM) algorithm. This measure is assessed via simulation study for the purpose of evaluating the utility of model fit. Further, several reconstructed adjusted coefficients of determination are proposed and compared via simulation study for the purpose of model selection. The application of these proposed measures is illustrated on a real dataset. 相似文献
2.
Tatjana Lichtenstein 《East European Jewish Affairs》2014,44(1):2-20
This article explores how perceptions of Jewish power shaped the negotiations between Czechoslovak leaders and Jewish minority representatives at the time of the Paris Peace Conference. In the aftermath of the First World War, Prague-based Zionists embarked on a mission to convince Czechoslovak elites that attacks on Jews were detrimental to the internal stability of the new state and to Czechoslovak interests abroad. As Edvard Bene?, the head of the Czechoslovak delegation in Paris, worked to cultivate an image of the new state as more “Western” and “civilised” than other successor states – a strategy meant to garner international support for Czechoslovak territorial demands and its projected absorption of large minority populations – Jewish activists encouraged his uncertainty with regard to Jews' influence on Western audiences and statesmen. They did so in order to convince him to accept their demands for special protection clauses for the new country's Jews. The paper thus shows that the unprecedented victimisation of Jews and the upsurge in antisemitism during and after the war coexisted with a new bold and public Jewish activism. Yet, Jewish leaders did not in the end have the ability to convince Bene? and his colleagues to give in to international Jewish demands for special protection. Instead, they sought to cultivate a strategic alliance between the state's Czech elite and the Jewish minority which centred on the claim that Czechoslovakia was a particularly welcoming and tolerant place for Jews, an image that would evolve into a significant component of the myth of Czechoslovakia as an island of democracy in Eastern Europe. 相似文献
3.
AbstractWe suggest shrinkage based technique for estimating covariance matrix in the high-dimensional normal model with missing data. Our approach is based on the monotone missing scheme assumption, meaning that missing values patterns occur completely at random. Our asymptotic framework allows the dimensionality p grow to infinity together with the sample size, N, and extends the methodology of Ledoit and Wolf (2004) to the case of two-step monotone missing data. Two new shrinkage-type estimators are derived and their dominance properties over the Ledoit and Wolf (2004) estimator are shown under the expected quadratic loss. We perform a simulation study and conclude that the proposed estimators are successful for a range of missing data scenarios. 相似文献
4.
There is a considerable amount of literature dealing with inference about the parameters in a heteroscedastic one-way random-effects ANOVA model. In this paper, we primarily address the problem of improved quadratic estimation of the random-effect variance component. It turns out that such estimators with a smaller mean squared error compared with some standard unbiased quadratic estimators exist under quite general conditions. Improved estimators of the error variance components are also established. 相似文献
5.
An intraclass correlation coefficient observed in several populations is estimated. The basis is a variance-stabilizing transformation. It is shown that the intraclass correlation coefficient from any elliptical distribution should be transformed in the same way. Four estimators are compared. An estimator where the components in a vector consisting of the transformed intraclass correlation coefficients are estimated separately, an estimator based on a weighted average of these components, a pretest estimator where the equality of the components is tested and then the outcome of the test is used in the estimation procedure, and a James-Stein estimator which shrinks toward the mean. 相似文献
6.
Tatjana Meschede Darrick Hamilton Ana Patricia Muñoz Regine Jackson William DarityJr. 《Race and social problems》2016,8(1):18-28
New data collected for the Boston Metropolitan Statistical Area provide detailed information on financial assets that allow analysis to extend beyond the traditional black–white divide. Targeting US-born blacks, Caribbean blacks, Puerto Ricans, Dominicans, and other Hispanics, findings from the National Asset Scorecard for Communities of Color survey underscore the large racial and ethnic disparities in financial wealth, even after controlling for demographic and socioeconomic status. Further, some notable differences between Boston’s communities of color highlight the importance of detailed analyses for research on the racial wealth gap. In particular, among non-white communities Dominicans report comparatively low asset and high debt amounts, while Caribbean blacks report relatively higher levels of wealth. Altogether, these findings point to the need for wealth building opportunities in communities of color and further investigation of the causes and consequences of financial disparities between groups of color disaggregated by specific ancestral origin. 相似文献
7.
We explore the performance accuracy of the linear and quadratic classifiers for high-dimensional higher-order data, assuming that the class conditional distributions are multivariate normal with locally doubly exchangeable covariance structure. We derive a two-stage procedure for estimating the covariance matrix: at the first stage, the Lasso-based structure learning is applied to sparsifying the block components within the covariance matrix. At the second stage, the maximum-likelihood estimators of all block-wise parameters are derived assuming the doubly exchangeable within block covariance structure and a Kronecker product structured mean vector. We also study the effect of the block size on the classification performance in the high-dimensional setting and derive a class of asymptotically equivalent block structure approximations, in a sense that the choice of the block size is asymptotically negligible. 相似文献
8.
Tatjana von Rosen 《统计学通讯:理论与方法》2020,49(13):3286-3297
AbstractSmall area estimation techniques have got a lot of attention during the last decades due to their important applications in survey studies. Mixed linear models and reduced rank regression analysis are jointly used when considering small area estimation. Estimates of parameters are presented as well as prediction of random effects and unobserved area measurements. 相似文献
9.
Gunnar Andersson Michaela Kreyenfeld Tatjana Mika 《Journal of Population Research》2014,31(4):287-316
This study investigates the role of female labour-market attachment and earnings in childbearing progressions in two very different European contexts. By applying event-history techniques to German and Danish register data during 1981–2001, we demonstrate how female earnings relate to first, second and third birth propensities. Our study shows that female earnings are positively associated with first birth fertility in Denmark, while this is not the case in West Germany. We interpret our findings based on the fact that Danish social context and policy encourage women to establish themselves in the labour market before becoming mothers, while the German institutional context during the 1980s and 1990s was not geared towards encouraging maternal employment. For higher-order births, the results are less clearcut. For Denmark we find a slightly positive correlation between female earnings and second-birth fertility, while the association is somewhat negative for third-order births. In Germany, women tend to leave the labour market when becoming mothers. Non-employed mothers have elevated second and, in particular, third-birth rates. For the group of mothers who are employed, we find only a weak association between their earnings and higher-order fertility. 相似文献
10.
Tatjana Takševa 《National Identities》2013,15(5):463-480
ABSTRACTRelying on the biographical narrative Leila, a girl from Bosnia and the recorded narratives by adolescents born of wartime rape in Bosnia and Herzegovina we illustrate the difficulties and symbolic implications associated with negotiating hybrid identities in post-conflict Bosnia and Herzegovina against the dominant post-conflict discourse based on ‘pure’ ethnicities. We argue that in today’s Bosnia and Herzegovina, hybrid identities are marginalized by official politics and societal structures as a legacy of the war. However, they simultaneously embody the symbolic tools through which ethnic divisions could be overcome, envisioning and recalling a multi-ethnic Bosnia and Herzegovina as a supra-national designation. 相似文献