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31.
32.
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
33.
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
34.
Burge E Kuhne N Berchtold A Maupetit C von Gunten A 《European review of aging and physical activity》2012,9(1):27-39
The objectives of this study were to describe the different modalities of physical activity programs designed for moderate
to severe dementia and to identify their impact on functional independence in activities of daily living (ADL). A critical
review of randomized controlled trials related to the impact of physical activity programs in moderately to severely demented
persons on ADL performance and meta-analysis of the identified studies were performed. Among the 303 identified articles,
five responded to the selection criteria. Four out of the five studies demonstrated limited methodological quality. In one
high-quality study, physical activity programs significantly delayed deterioration of ADL performance. The program components
and ADL assessment tools vary widely across studies. Although the proposed treatments have not proven their efficiency in
improving the ADL status of the patients, they were able to limit the decline in ADL functioning. Future research is warranted
in order to identify clinically relevant modalities for physical activity programs for people with moderate to severe dementia. 相似文献
35.
36.
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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37.
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
38.
Young children are extremely motivated to help others, but it is not clear whether they do so in anonymous situations without social recognition. In two studies, we found that 18‐month‐old toddlers provided help equally in situations where an adult recipient was present and in situations where an adult recipient was not present. We included several control conditions to rule out that toddlers were simply unaware of their anonymity or were merely motivated to restore the physical order of things. Together, these findings suggest that early in ontogeny children are motivated to help others in need regardless of whether they can immediately be recognized for their prosocial intentions. 相似文献
39.
This work presents a study about the smoothness attained by the methods more frequently used to choose the smoothing parameter in the context of splines: Cross Validation, Generalized Cross Validation, and corrected Akaike and Bayesian Information Criteria, implemented with Penalized Least Squares. It is concluded that the amount of smoothness strongly depends on the length of the series and on the type of underlying trend, while the presence of seasonality even though statistically significant is less relevant. The intrinsic variability of the series is not statistically significant and its effect is taken into account only through the smoothing parameter. 相似文献
40.
For estimating an unknown parameter θ, we introduce and motivate the use of balanced loss functions of the form Lr, w, d0(q, d)=wr(d0, d)+ (1-w) r(q, d){L_{\rho, \omega, \delta_0}(\theta, \delta)=\omega \rho(\delta_0, \delta)+ (1-\omega) \rho(\theta, \delta)}, as well as the weighted version q(q) Lr, w, d0(q, d){q(\theta) L_{\rho, \omega, \delta_0}(\theta, \delta)}, where ρ(θ, δ) is an arbitrary loss function, δ
0 is a chosen a priori “target” estimator of q, w ? [0,1){\theta, \omega \in[0,1)}, and q(·) is a positive weight function. we develop Bayesian estimators under Lr, w, d0{L_{\rho, \omega, \delta_0}} with ω > 0 by relating such estimators to Bayesian solutions under Lr, w, d0{L_{\rho, \omega, \delta_0}} with ω = 0. Illustrations are given for various choices of ρ, such as absolute value, entropy, linex, and squared error type losses. Finally, under various robust Bayesian analysis criteria
including posterior regret gamma-minimaxity, conditional gamma-minimaxity, and most stable, we establish explicit connections
between optimal actions derived under balanced and unbalanced losses. 相似文献