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721.
基于推荐系统中协同过滤推荐的思想, 提出两种可以利用已有答题者数据的CAT选题策略:直接基于答题者推荐(DEBR)和间接基于答题者推荐(IEBR)。通过两个模拟研究, 在不同题库和不同长度的测验中, 比较了两种推荐选题策略与两种传统选题策略(FMI和BAS)在测量精度和对题目曝光率控制上的表现, 以及影响推荐选题策略表现的因素。结果发现:两种推荐选题策略对题目曝光率的控制优于两种传统选题策略, 测量精度不亚于BAS方法, 其中DEBR侧重选题精度, IEBR对题目曝光率控制最好。已有答题者数据的特点和质量是影响推荐选题策略表现的主要因素。 相似文献
722.
A bicycle helmet program was evaluated in three middle schools using a multiple baseline across schools design. Two of the three schools had histories of enforcement of helmet use. During baseline many students riding their bikes to and from school did not wear their helmets or wore them incorrectly. A program that consisted of peer data collection of correct helmet use, education on how to wear a bicycle helmet correctly, peer goal setting, public posting of the percentage of correct helmet use, and shared reinforcers, all of which were implemented by the school resource officer, increased afternoon helmet use and afternoon correct helmet use in all three schools. Probe data collected a distance from all three schools indicated that students did not remove their helmets once they were no longer in close proximity to the school, and probe data collected in the morning at two of the schools showed that the behavior change transferred to the morning. 相似文献
723.
The clustering of two-mode proximity matrices is a challenging combinatorial optimization problem that has important applications in the quantitative social sciences. We focus on one particular type of problem related to the clustering of a two-mode binary matrix, which is relevant to the establishment of generalized blockmodels for social networks. In this context, clusters for the rows of the two-mode matrix intersect with clusters of the columns to form blocks, which should ideally be either complete (all 1s) or null (all 0s). A new procedure based on variable neighborhood search is presented and compared to an existing two-mode K-means clustering algorithm. The new procedure generally provided slightly greater explained variation; however, both methods yielded exceptional recovery of cluster structure. 相似文献
724.
A Measure for the Reliability of a Rating Scale Based on Longitudinal Clinical Trial Data 总被引:2,自引:1,他引:1
A new measure for reliability of a rating scale is introduced, based on the classical definition of reliability, as the ratio
of the true score variance and the total variance. Clinical trial data can be employed to estimate the reliability of the
scale in use, whenever repeated measurements are taken. The reliability is estimated from the covariance parameters obtained
from a linear mixed model. The method provides a single number to express the reliability of the scale, but allows for the
study of the reliability’s time evolution. The method is illustrated using a case study in schizophrenia.
The authors are grateful to J&J PRD for kind permission to use their data. We gratefully acknowledge support from the Belgian
IUAP/PAI network “Statistical Techniques and Modeling for Complex Substantive Questions with Complex Data.” 相似文献
725.
Hierarchical Classes Modeling of Rating Data 总被引:2,自引:1,他引:1
Hierarchical classes (HICLAS) models constitute a distinct family of structural models for N-way N-mode data. All members of the family include N simultaneous and linked classifications of the elements of the N modes implied by the data; those classifications are organized in terms of hierarchical, if–then-type relations. Moreover,
the models are accompanied by comprehensive, insightful graphical representations. Up to now, the hierarchical classes family
has been limited to dichotomous or dichotomized data. In the present paper we propose a novel extension of the family to two-way
two-mode rating data (HICLAS-R). The HICLAS-R model preserves the representation of simultaneous and linked classifications
as well as of generalized if–then-type relations, and keeps being accompanied by a comprehensive graphical representation.
It is shown to bear interesting relationships with classical real-valued two-way component analysis and with methods of optimal
scaling.
The research reported in this paper was supported by the Research Fund of the University of Leuven (GOA/00/02 and GOA/05/04)
and by the Fund for Scientific Research-Flanders (project G.0146.06). Eva Ceulemans is a Post-doctoral Researcher supported
by the Fund for Scientific Research, Flanders. The authors gratefully acknowledge the help of Gert Quintiens and Kaatje Bollaerts
in collecting the data used in Section 4 and of Jan Schepers in additional analyses of these data. 相似文献
726.
Vartan Choulakian 《Psychometrika》1988,53(2):235-250
Goodman's (1979, 1981, 1985) loglinear formulation for bi-way contingency tables is extended to tables with or without missing cells and is used for exploratory purposes. A similar formulation is done for three-way tables and generalizations of correspondence analysis are deduced. A generalized version of Goodman's algorithm, based on Newton's elementary unidimensional method is used to estimate the scores in all cases.This research was partially supported by National Science and Engineering Research Council of Canada, Grant No. A8724. The author is grateful to the reviewers and the editor for helpful comments. 相似文献
727.
728.
Hierarchical classes models for three-way three-mode binary data: interrelations and model selection
Several hierarchical classes models can be considered for the modeling of three-way three-mode binary data, including the INDCLAS model (Leenen, Van Mechelen, De Boeck, and Rosenberg, 1999), the Tucker3-HICLAS model (Ceulemans, Van Mechelen, and Leenen, 2003), the Tucker2-HICLAS model (Ceulemans and Van Mechelen, 2004), and the Tucker1-HICLAS model that is introduced in this paper. Two questions then may be raised: (1) how are these models interrelated, and (2) given a specific data set, which of these models should be selected, and in which rank? In the present paper, we deal with these questions by (1) showing that the distinct hierarchical classes models for three-way three-mode binary data can be organized into a partially ordered hierarchy, and (2) by presenting model selection strategies based on extensions of the well-known scree test and on the Akaike information criterion. The latter strategies are evaluated by means of an extensive simulation study and are illustrated with an application to interpersonal emotion data. Finally, the presented hierarchy and model selection strategies are related to corresponding work by Kiers (1991) for principal component models for three-way three-mode real-valued data. 相似文献
729.
将高中生化学问题解决思维过程口语报告分为相应的10个行为指标进行人工编码和定量分析。被试是56名高中生,材料为6个中等难度的化学问题,通过“出声思考”实验,记录口语报告,并对口语报告进行编码和数据统计分析,结果发现:(1)高中优生的重复、解释、推理、归纳、总结等行为指标上明显优于中等生;(2)在解决不同类型的化学问题时,重复、设问、推理、归纳和反思等指标存在明显差异;(3)学生能力层次与问题类别在重复、推理、归纳和试误等行为指标上存在明显交互作用。 相似文献
730.
Oliveira-Castro JM Foxall GR Schrezenmaier TC 《Journal of the experimental analysis of behavior》2006,85(2):147-166
Following the behavior-analytic tradition of analyzing individual behavior, the present research investigated demand elasticity of individual consumers purchasing supermarket products, and compared individual and group analyses of elasticity. Panel data from 80 UK consumers purchasing 9 product categories (i.e., baked beans, biscuits, breakfast cereals, butter, cheese, fruit juice, instant coffee, margarine and tea) during a 16-week period were used. Elasticity coefficients were calculated for individual consumers with data from all or only 1 product category (intra-consumer elasticities), and for each product category using all data points from all consumers (overall product elasticity) or 1 average data point per consumer (interconsumer elasticity). In addition to this, split-sample elasticity coefficients were obtained for each individual with data from all product categories purchased during weeks 1 to 8 and 9 to 16. The results suggest that: 1) demand elasticity coefficients calculated for individual consumers purchasing supermarket food products are compatible with predictions from economic theory and behavioral economics; 2) overall product elasticities, typically employed in marketing and econometric research, include effects of interconsumer and intraconsumer elasticities; 3) when comparing demand elasticities of different product categories, group and individual analyses yield similar trends; and 4) individual differences in demand elasticity are relatively consistent across time, but do not seem to be consistent across products. These results demonstrate the theoretical, methodological, and managerial relevance of investigating the behavior of individual consumers. 相似文献