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941.
Nicolas Guéguen Lubomir Lamy 《Journal Of Human Behavior In The Social Environment》2013,23(3):383-387
Previous research found that survey response rates were influenced by physical characteristics of the interviewer. However, the effect of hair color on compliance to a survey request has never been studied. Female confederates wearing blond, brown, black, or red wigs solicited 1,200 male and female pedestrians for a survey. It was found those male passersby, but not the female, agreed more frequently to the confederates wearing blond wigs whereas they agreed less to the same confederates wearing red wigs. Greater youth and healthiness associated with blond hair in women is used to explain these results. The practical interest in face-to-face surveys is addressed. 相似文献
942.
Brandi N. Hawk Amanda Wright Megan M. Julian Johana M. Rosas Emily C. Merz Robert B. McCall 《Adoption quarterly》2013,16(2):97-107
This study assesses selective responding in a single wave of data collection and a four-wave study. Participants were 121 parents of post-institutionalized children, identified as “never responders,” “previous responders,” or “wave 4 responders.” Parents evaluated their adopted child's family, school, peer, and behavioral adjustment. Children (47% male) were 2 to 20 years old (M = 10.79, SD = 4.59) and adopted between 5 and 54 months of age (M = 15.49, SD = 9.94). Within a single wave of data collection, no evidence suggested that selective responding contributes much bias. Over a multi-wave study, however, results may under-represent adjustment difficulties. 相似文献
943.
The objective of this study was to evaluate the shape of anterior–posterior curvatures of the spine and to determine the values of body symmetry deviations in the frontal plane, in elderly males. The study group consisted of 34 males aged between 61 and 83 years, attending two hour-long training sessions a week. The comparative group consisted of 30 students. The photogrammetric method based on the Moire phenomenon was used to evaluate the body posture. The obtained data confirm characteristic tendencies of physiological spinal curvatures to change with the aging process. A decrease of the lumbar–sacral spinal-segment inclination and an increase of the upper thoracic spinal-segment inclination were observed in the elderly males. Whereas, the value of thoracic kyphosis lower-segment inclination was similar to the value obtained in young adult males. The stated differences indicate a flattening of lumbar lordosis and a deepening of the upper arch of thoracic kyphosis, which results in a characteristic body posture in the standing position with the head protruding and the upper trunk segment inclined. The above-mentioned observations indicate a dominance of the angular thoracic kyphosis value over the remaining spinal curvatures. These differences occur to a greater degree in elderly males. 相似文献
944.
945.
William C. Guenther 《The American statistician》2013,67(3):120-121
An elementary method of proof of the mode, median, and mean inequality is given for skewed, unimodal distributions of continuous random variables. A proof of the inequality for the gamma, F, and beta random variables is sketched. 相似文献
946.
947.
The Consistent System (CS) is an interactive computer system for researchers in the behavioral and policy sciences and in fields with similar requirements for data management and statistical analysis. The researcher is not expected to be a programmer. The system offers a wide range of facilities and permits the user to combine them in novel ways. In particular, tools for statistical analysis may be used in combination with a powerful relational subsystem for data base management. This paper gives an overview of the objectives, capabilities, status, and availability of the system. 相似文献
948.
A. C. Braga L. Costa P. Oliveira 《Journal of Statistical Computation and Simulation》2013,83(2):307-325
In this paper, an alternative method for the comparison of two diagnostic systems based on receiver operating characteristic (ROC) curves is presented. ROC curve analysis is often used as a statistical tool for the evaluation of diagnostic systems. However, in general, the comparison of ROC curves is not straightforward, in particular, when they cross each other. A similar difficulty is also observed in the multi-objective optimization field where sets of solutions defining fronts must be compared with a multi-dimensional space. Thus, the proposed methodology is based on a procedure used to compare the performance of distinct multi-objective optimization algorithms. In general, methods based on the area under the ROC curves are not sensitive to the existence of crossing points between the curves. The new approach can deal with this situation and also allows the comparison of partial portions of ROC curves according to particular values of sensitivity and specificity of practical interest. Simulations results are presented. For illustration purposes, considering real data from newborns with very low birthweight, the new method was applied in order to discriminate the better index for evaluating the risk of death. 相似文献
949.
Virginia C. Haines 《Serials Review》2013,39(2):103-108
AbstractIn March 2001 the Canadian National Site Licensing Project (CNSLP) enabled the University of Saskatchewan Library to add over seven hundred electronic titles to its journal collection. The CNSLP titles introduced a critical mass of electronic journals to library patrons, offering a complex and intriguing range of supplementary content and a transformation of the experience of reading scientific journals. This article reports on the plug-ins and add-ons required to access supplementary content in the CNSLP electronic journals and explores the implications of supplementary content for readers. Serials Review 2003; 29:103–116. 相似文献
950.
k-POD: A Method for k-Means Clustering of Missing Data 总被引:1,自引:0,他引:1
The k-means algorithm is often used in clustering applications but its usage requires a complete data matrix. Missing data, however, are common in many applications. Mainstream approaches to clustering missing data reduce the missing data problem to a complete data formulation through either deletion or imputation but these solutions may incur significant costs. Our k-POD method presents a simple extension of k-means clustering for missing data that works even when the missingness mechanism is unknown, when external information is unavailable, and when there is significant missingness in the data.[Received November 2014. Revised August 2015.] 相似文献