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991.
This paper considers total and direct effects in linear structural equation models. Adopting a causal perspective that is implicit in much of the literature on the subject, the paper concludes that in many instances the effects do not admit the interpretations imparted in the literature. Drawing a distinction between concomitants and factors, the paper concludes that a concomitant has neither total nor direct effects on other variables. When a variable is a factor and one or more intervening variables are concomitants, the notion of a direct effect is not causally meaningful. Even when the notion of a direct effect is meaningful, the usual estimate of this quantity may be inappropriate. The total effect is usually interpreted as an equilibrium multiplier. In the case where there are simultaneity relations among the dependent variables in tghe model, the results in the literature for the total effects of dependent variables on other dependent variables are not equilibrium multipliers, and thus, the usual interpretation is incorrect. To remedy some of these deficiencies, a new effect, the total effect of a factorX on an outcomeY, holding a set of variablesF constant, is defined. When defined, the total and direct effects are a special case of this new effect, and the total effect of a dependent variable on a dependent variable is an equilibrium multiplier.For helpful comments, I am grateful to G. Arminger, K. Bollen, W. Faris, R. m. Hauser, T. Petersen, three anonymous Psychometrikas reviewers, and the Editor. For computational assistance, I am grateful to B. D. Kim.  相似文献   
992.
An estimate and an upper-bound estimate for the reliability of a test composed of binary items is derived from the multidimensional latent trait theory proposed by Bock and Aitkin (1981). The estimate derived here is similar to internal consistency estimates (such as coefficient alpha) in that it is a function of the correlations among test items; however, it is not a lowerbound estimate as are all other similar methods.An upper bound to reliability that is less than unity does not exist in the context of classical test theory. The richer theoretical background provided by Bock and Aitkin's latent trait model has allowed the development of an index (called here) that is always greater-than or equal-to the reliability coefficient for a test (and is less-than or equal-to one). The upper bound estimate of reliability has practical uses—one of which makes use of the greatest lower bound.  相似文献   
993.
The possibility of obtaining locally optimal solutions with categorical data is pointed out for the original version of OSMOD development by Saito and Otsu. A revision of the initialization strategy in OSMOD is suggested, and its effectiveness in diminishing this possibility is demonstrated.  相似文献   
994.
Yutaka Kano 《Psychometrika》1990,55(2):277-291
Based on the usual factor analysis model, this paper investigates the relationship between improper solutions and the number of factors, and discusses the properties of the noniterative estimation method of Ihara and Kano in exploratory factor analysis. The consistency of the Ihara and Kano estimator is shown to hold even for an overestimated number of factors, which provides a theoretical basis for the rare occurrence of improper solutions and for a new method of choosing the number of factors. The comparative study of their estimator and that based on maximum likelihood is carried out by a Monte Carlo experiment.The author would like to express his thanks to Masashi Okamoto and Masamori Ihara for helpful comments and to the editor and referees for critically reading the earlier versions and making many valuable suggestions. He also thanks Shigeo Aki for his comments on physical random numbers.  相似文献   
995.
To uphold the distinction between perception and cognition for certain classes of tasks or phenomena, it is proposed that three criteria must be met: (1) when perceptual and cognitive functions serve different biological purposes, (2) when stimulus information in dynamic events is necessary, but not sufficient for veridical perception, and (3) when the task emphasizes explicit retrieval, as opposed to implicit use of information. Conversely, when the three criteria have not been met, conditions for theoretical unification exist.  相似文献   
996.
Use of the Cognitive Failures Questionnaire (CFQ) in clinical research assumes that the questionnaire measures a single factor. A factor analysis of the CFQ was performed, on a sample of 475 students, using accurate procedures for determining the number of factors. These procedures gave mutually inconsistent results: at least two alternative factor structures can be extracted from the CFQ. An interpretable seven factor solution was found, but the CFQ probably has insufficient items to measure more than two strongly defined factors. The capacity of CFQ multiple factors to predict measures related to stress vulnerability was tested in a further study (N=57). Correlations between CFQ total score and neuroticism and use of coping strategies appeared to depend mainly on a single CFQ multiple factor, related to failures of concentration. Some of the other CFQ factors predicted other criteria. Further research on multiple factors of cognitive failure might improve the validity of the CFQ as a predictor of stress vulnerability and of cognitive performance.  相似文献   
997.
The purpose of the study was to determine the factor structure of the revised Multiple Affect Adjective Check List (MAACL-R). The data from 307 undergraduate students who completed the MAACL-R were factor analyzed using both principal-components and principal-axis techniques. Based upon research with the original MAACL, two- and five-factor solutions to the MAACL-R factor structure were examined. The principal-components and principal-axis techniques yielded similar item loadings for each solution and the results of both techniques indicated the superiority of the two-factor solution. The two identified factors could be best characterized as representing independent dimensions of negative and positive affect. These findings are interpreted as providing support for the use of the MAACL-R summary scores of Dysphoria and PASS (Positive Affect and Sensation Seeking) rather than for the use of the five MAACL-R subscales.  相似文献   
998.
Development and analysis of a community-based resource recovery program   总被引:1,自引:0,他引:1  
Five studies were conducted over a 10-month period to determine the effectiveness of specific procedures in encouraging recycling among residential neighborhoods. Results indicated that: (a) initial levels of participation in neighborhoods were frequently related to housing values; (b) weekly recycling pick-ups that coincided with garbage collection days resulted in higher levels of participation than pick-ups that occurred at other times; (c) notifying homes about the recycling program through distributed door-to-door brochures was more effective than soliciting participation through newspaper ads; (d) distributing containers to help residents separate recyclable from nonrecyclable material proved to be an effective procedure, especially when combined with frequent prompting (prompting alone did not have much effect); and (e) procedures that facilitated the greatest levels of participation were not always cost-effective. The subsequent combination of these procedures into a package program resulted in high levels of neighborhood participation that were cost-effective and maintained over a 6-month period.  相似文献   
999.
The extent to which interrater agreement and ratings of significance on both changes in level and trend are affected by lines of progress and semilogarithmic charts was investigated. Thirteen graduate students rated four sets of charts, each set containing 19 phase changes. Set I data were plotted on equal interval charts. In Set II a line of progress was drawn through each phase on each chart. In Set III data points were replotted on semilogarithmic charts. In Set IV a line of progress was drawn through each phase of each Set III chart. A significant main effect on interrater agreement was found for lines of progress as well as a significant 2-way interaction between lines of progress and change type. Three main effects (chart type, lines of progress, and type of change) and a significant 3-way interaction were found for ratings of significance. Implications of these data for visual analysis of charted data are discussed.  相似文献   
1000.
Although considerable attention has been given to the development of institutional staff training and management programs, the generalized effects of such programs on staff and resident behavior have seldom been examined. This study evaluated a program for teaching institutional staff behavioral training and self-management skills during self-care teaching sessions with severely and profoundly retarded residents. Following baseline observations in three self-care situations (toothbrushing, haircombing, handwashing), four direct care staff were sequentially taught to use verbal instruction, physical guidance, and contingent reinforcement in the toothbrushing program. During maintenance, staff were simultaneously taught to record, graph, and evaluate resident and their own behavior in the toothbrushing sessions. Staff were taught use of the training and self-management skills through a sequence of written instructions, videotaped and live modeling, rehearsal, and videotaped feedback. Observer presence and experimenter supervision were gradually decreased during the maintenance condition. Results indicated that during training and maintenance staff: (a) learned to use the training skills appropriately and consistently in the example situation (toothbrushing); (b) applied the skills in the generalization situations (haircombing and handwashing); and thereafter (c) maintained consistent and appropriate use of the skills with infrequent supervision. In addition, important changes in retarded residents' independent self-care responding occurred as staff training skills developed. Results are discussed in terms of their implication for future research and continued development of effective staff training and management programs.  相似文献   
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