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91.
To compare two modes of administration (self-administered; by interviewer) and two response options format (using words; images
of “facial-expressions”) of the first question of SF-36 (Q1SF-36), and to test its validity. We included 825 participants
(20–90 years). Q1SF-36, using words or images, was included in a global questionnaire interview and at the end participants
filled the SF-36. The agreement was tested by weighted kappa coefficients (WKappa). Classification Trees were used in the
calibration of Q1SF-36 responses, with the physical (PDSF36) and mental dimensions of SF-36. Polyserial correlation coefficients
and areas under the ROC curves (AUC) were used for validation. After categorization, using PDSF36 classification trees, the
WKappa were 0.770 (self-administered vs. interviewer), 0.569 (self-administered vs. facial-expressions) and 0.566 (interviewer
vs. facial-expressions). The WKappa between the PDSF36 and the modes (self-administered, interviewer and facial-expressions)
were 0.784, 0.713 and 0.579 and the corresponding polyserial correlation coefficients were 0.784, 0.713 and 0.579. A good
discriminatory power was found comparing the modes with the PDSF36 (AUC = 0.907, 0.923 and 0.827), but not with mental dimension
(AUC = 0.538, 0.501 and 0.629). The Q1SF-36, by self-administration or interviewer, may be a valid alternative for assessment
of subjective physical health, but not mental health. 相似文献
92.
Nathalie Villa-Vialaneix Noslen Hernández Alain Paris Céline Domange Nathalie Priymenko Philippe Besse 《统计学通讯:模拟与计算》2016,45(1):282-298
Wavelet thresholding of spectra has to be handled with care when the spectra are the predictors of a regression problem. Indeed, a blind thresholding of the signal followed by a regression method often leads to deteriorated predictions. The scope of this article is to show that sparse regression methods, applied in the wavelet domain, perform an automatic thresholding: the most relevant wavelet coefficients are selected to optimize the prediction of a given target of interest. This approach can be seen as a joint thresholding designed for a predictive purpose. The method is illustrated on a real world problem where metabolomic data are linked to poison ingestion. This example proves the usefulness of wavelet expansion and the good behavior of sparse and regularized methods. A comparison study is performed between the two-steps approach (wavelet thresholding and regression) and the one-step approach (selection of wavelet coefficients with a sparse regression). The comparison includes two types of wavelet bases, various thresholding methods, and various regression methods and is evaluated by calculating prediction performances. Information about the location of the most important features on the spectra was also obtained and used to identify the most relevant metabolites involved in the mice poisoning. 相似文献
93.
Alena Bičáková 《Journal of Labor Research》2017,38(4):428-438
Previous research has documented the impact of positive selection into employment on the ranking of countries by gender wage gaps. This note focuses on the impact of selection into labor force on cross-country differences in gender unemployment gaps. We construct the Manski bounds for the selection-free gender unemployment gaps in 26 EU countries and show that - without additional assumptions - the observed gender unemployment gaps carry little information about the selection-free gender differences in unemployment. Contrary to the common assumption of positive selection into labor force (similar to positive selection into employment documented in the gender wage gap research), we also point at an example of negative-selection bias. We show that labor force withdrawal of mothers on job-protected family leaves may lead to an overestimation of the selection-free gender unemployment gaps by as much as 1 p.p. 相似文献
94.
Anthropogenic climate change information tends to be interpreted against the backdrop of initial environmental beliefs, which can lead to some people being resistant toward the information. In this article (N = 88), we examined whether self‐affirmation via reflection on personally important values could attenuate the impact of initial beliefs on the acceptance of anthropogenic climate change evidence. Our findings showed that initial beliefs about the human impact on ecological stability influenced the acceptance of information only among nonaffirmed participants. Self‐affirmed participants who were initially resistant toward the information showed stronger beliefs in the existence of climate change risks and greater acknowledgment that individual efficacy has a role to play in reducing climate change risks than did their nonaffirmed counterparts. 相似文献
95.
Bayesian Networks: With Examples in R. By M. Scutari and J.‐B. Denis Boca Raton,Florida CRC Press. 2014. 241 pages. UK £69.99 (hardback). ISBN 978‐1‐48222‐558‐7
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96.
Janet Boddy June Statham Inge Danielsen Esther Geurts Hélène Join‐Lambert Sévèrine Euillet 《Children & Society》2014,28(2):152-161
In England, placement within the looked after system is not viewed as a desirable long‐term solution for most children, and policy has prioritised continued contact with parents, and swift return home, wherever possible. This review examines policy approaches to work with families of looked after children in England and in three other European countries: Denmark, France and the Netherlands, aiming to identify areas for shared learning in relation to this challenging area of policy and practice. The research highlights relationships between care populations and policy understandings of the purpose of work with families, including understandings of children's and/or parents’ rights. 相似文献
97.
沈阳市棋盘山风景区西北方向,进正门直行,最后一个交通岗右转4.2公里,可见一座颇具气势的展馆,建筑面积有1万余平方米.
此馆名为“中华饮食文化博物馆”,展示的乃是悠悠华夏饮食文化,馆内展品林林总总,自新石器时代开始至现代的炊具、食具,最原始的石磨、陶灶,到瓷器辉煌时期宋代的天目盏,又有各种精致食材的标本.无一不是精品,无一不是舌尖上的浓缩.
有这样一座以饮食文化为主题的博物馆,馆长一定不是普通人,这个人是著名辽菜大师李春祥. 相似文献
98.
The asymptotic variance of the maximum likelihood estimate is proved to decrease when the maximization is restricted to a subspace that contains the true parameter value. Maximum likelihood estimation allows a systematic fitting of covariance models to the sample, which is important in data assimilation. The hierarchical maximum likelihood approach is applied to the spectral diagonal covariance model with different parameterizations of eigenvalue decay, and to the sparse inverse covariance model with specified parameter values on different sets of nonzero entries. It is shown computationally that using smaller sets of parameters can decrease the sampling noise in high dimension substantially. 相似文献
99.
100.
Jin-Feng Wang Yi-Lan Liao Jiao-Jiao Wang Jie Fan Tian Chen Xiao-Lu Gao Zhi-Dong Cao Mao-Gui Hu Yong Ge Xiao-Ying Zheng 《Population and environment》2012,33(2-3):233-242
Natural catastrophes such as earthquakes can, in addition to causing loss of life, disrupt the urbanization process through the need for forced population redistribution and the modification of resource and environmental carrying capacity. The population carrying capacity (PCC) of an altered environment following an earthquake is a crucial determinant in the relocation of displaced persons. We use data adaptive methods to model the correlation between the physical environment and human population density in estimating PCC in areas affected by the 2008 Wenchuan earthquake. Comparing actual population distributions with ideal population distributions allows for the identification of villages where population exceeds PCC, or conversely, areas where the environment can support a higher population. Such a comparison can provide the basis for a relocation plan, a critical element of post-catastrophe policy-making. 相似文献