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41.
Momentary maximizing in concurrent schedules with a minimum interchangeover interval 总被引:2,自引:2,他引:0 下载免费PDF全文
Eight pigeons were trained on concurrent variable-interval variable-interval schedules with a minimum interchangeover time programmed as a consequence of changeovers. In Experiment 1 the reinforcement schedules remained constant while the minimum interchangeover time varied from 0 to 200 s. Relative response rates and relative time deviated from relative reinforcement rates toward indifference with long minimum interchangeover times. In Experiment 2 different reinforcement ratios were scheduled in successive experimental conditions with the minimum interchangeover time constant at 0, 2, 10, or 120 s. The exponent of the generalized matching equation was close to 1.0 when the minimum interchangeover time was 0 s (the typical procedure for concurrent schedules without a changeover delay) and decreased as that duration was increased. The data support the momentary maximizing theory and contradict molar maximizing theories and the melioration theory. 相似文献
42.
Robert F. Fagot 《Psychometrika》1993,58(2):357-370
A family of coefficients of relational agreement for numerical scales is proposed. The theory is a generalization to multiple judges of the Zegers and ten Berge theory of association coefficients for two variables and is based on the premise that the choice of a coefficient depends on the scale type of the variables, defined by the class of admissible transformations. Coefficients of relational agreement that denote agreement with respect to empirically meaningful relationships are derived for absolute, ratio, interval, and additive scales. The proposed theory is compared to intraclass correlation, and it is shown that the coefficient of additivity is identical to one measure of intraclass correlation.The author thanks the Editor and anonymous reviewers for helpful suggestions. 相似文献
43.
Interpreting canonical correlation analysis through biplots of structure correlations and weights 总被引:1,自引:0,他引:1
Cajo J. F. ter Braak 《Psychometrika》1990,55(3):519-531
This paper extends the biplot technique to canonical correlation analysis and redundancy analysis. The plot of structure correlations is shown to the optimal for displaying the pairwise correlations between the variables of the one set and those of the second. The link between multivariate regression and canonical correlation analysis/redundancy analysis is exploited for producing an optimal biplot that displays a matrix of regression coefficients. This plot can be made from the canonical weights of the predictors and the structure correlations of the criterion variables. An example is used to show how the proposed biplots may be interpreted. 相似文献
44.
We derive several relationships between communalities and the eigenvalues for ap ×p correlation matrix under the usual factor analysis model. For suitable choices ofj,
j
(), where
j
() is thej-th largest eigenvalue of , provides either a lower or an upper bound to the communalities for some of the variables. We show that for at least one variable, 1 -
p
() improves on the use of squared mulitiple correlation coefficient as a lower bound.This research was done while the second author was at Tokyo Institute of Technology. 相似文献
45.
The purpose of the study was to investigate occupational stress among Chinese factory workers (N=342), from three cities of South East China, using the shortened version of the Occupational Stress Indicator (OSI)-2. The
results showed that the reliabilities and predictive validity of the OSI-2 subscales and other subscales used for the study
were reasonably high. Quite a high percentage of workers perceived high work pressure. The main sources of stress were intrinsic
to the job; and the coping strategies that were most frequently used to tackle stress were “control” methods. In addition,
“satisfaction on environmental condition” seemed to be a common predictor for job satisfaction, and mental and physical well-being.
The logical relationships between job satisfaction, mental well-being and physical well-being in Chinese workers have provided
support to the findings obtained in Western countries. 相似文献
46.
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49.
Math J. J. M. Candel 《Psychometrika》1997,62(1):119-131
Arrangements of feature sets that have been proposed to represent qualitative and quantitative variation among objects are shown to generate identical sets of set-symmetric distances. The set-symmetric distances for these feature arrangements can be represented by path lengths in an additive linear tree. Imperfect versions of these feature arrangements are proposed, which also are indistinguishable by the set-symmetric distance model. The distances for the imperfect versions can be represented by path lengths in an additive imperfectly linear tree. When dissimilarities are defined by the more general contrast model and a constant may be added to proximity data, then for both the perfect and imperfect arrangements an additive tree analysis obtains a perfect fit with an imperfectly linear tree. However, in the case of the contrast model also the distinction between the perfect and imperfect arrangements disappears in that also for the perfect arrangements the resulting tree need no longer be linear.The author is grateful to Mathieu Koppen for detailed comments on an earlier version of this article. 相似文献
50.
Shrinkage estimation of linear combinations of true scores 总被引:1,自引:0,他引:1
Nicholas T. Longford 《Psychometrika》1997,62(2):237-244
This paper is concerned with combining observed scores from sections of tests. It is demonstrated that in the presence of population information a linear combination of true scores can be estimated more efficiently than by the same linear combination of the observed scores. Three criteria for optimality are discussed, but they yield the same solution which can be described and motivated as a multivariate shrinkage estimator.Input from Eric Bradlow, Charles Lewis, and Linda Zeger is acknowledged. Research for this paper was funded by the Program Research Council (ETS). Suggestions of the Editor and of anonymous referees were instrumental in several improvements of the paper. 相似文献