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881.
Considerations of factor score estimates have concentrated on internal characteristics. This report considers external characteristics of four methods for determining factor score estimates; that is, relations of these estimates to measures on attributes not entered into the factor analysis. These external characteristics are important for many uses of factor score estimates. Findings are that different ones of the methods are appropriate for different uses.Supported in part by the Personnel and Training Branch of the Office of Naval Research under contract number 00014-67-A-0305-0003.  相似文献   
882.
Previous research on the renal conditional reflex (CR) has resulted in contradictory data. The work of Bykov with dogs and of Hoferet al. with humans indicated that a renal CR is possible, but the experiments of Corsonet al. and Watt and Gantt with dogs having normal or transplanted cervical kidneys showed no clear-cut renal CR’s. The present work supports the latter finding. Three female mongrel dogs were used. One dog (normal) had an externalized ureter; the other two (experimental) had denervated cervical kidneys (autografts). In 155 days of experiments, the investigators found diuresis to occur only on unconditional stimulus,i.e., only when a dog drank diluted milk (one part milk to four parts water)ad lib.; the dogs drank an average of between 500 and 1,100 ml. No diuresis occurred when 30 ml. of the mixture were given (conditional stimulus). Urinalysis indicated a lack of renal conditioning with respect to the excretion rates and the concentrations of creatinine and electrolytes, except for the sodium concentration in the normal dog’s urine, which decreased on bothad lib and test (30 ml) days; the volume was not affected. Conclusion: Drinking a small quantity of diluted milk as a conditional stimulus did not produce a conditional diuretic response either in the normal dog or in the two dogs with transplanted kidneys.  相似文献   
883.
An individual differences model for multidimensional scaling   总被引:3,自引:0,他引:3  
A quantitative system is presented to permit the determination of separate multidimensional perceptual spaces for individuals having different viewpoints about stimulus interrelationships. The structure of individual differences in the perception of stimulus relationships is also determined to provide a framework for ascertaining the varieties of consistent individual viewpoints and their relationships with other variables.This research was supported in part by the National Institute of Mental Health, United States Public Health Service, under Research Grants M-2878 and M-4186 to Educational Testing Service, in part by Educational Testing Service, and in part by the Office of Naval Research under Contract Nonr-1834(39) and the University of Illinois. The authors wish to thank Drs. Harold Gulliksen and Douglas N. Jackson for their helpful comments and Miss Henrietta Gallagher for supervising the computations. Portions of this paper were presented at the American Psychological Association meetings in Chicago, September 1960.This paper was written while Dr. Messick was a Fellow at the Center for Advanced Study in the Behavioral Sciences.  相似文献   
884.
The problem of solving simultaneous linear equations is one that frequently confronts the scientist. Whenever it is desired to state the parameters as expressions of the constant terms of these equations, the problem resolves itself into the discovery of the inverse of the matrix of coefficients. The method here described gives a routine for the solution of this problem.  相似文献   
885.
Television's role regarding alcohol use among teenagers   总被引:1,自引:0,他引:1  
L A Tucker 《Adolescence》1985,20(79):593-598
The purpose of this study was to determine the extent to which adolescents classified as light, moderate, or heavy television viewers differ regarding alcohol use. The extent to which demographic variables mediate the television-alcohol association also was investigated. A total of 394 high school males completed a written questionnaire to assess television and drinking practices. As hypothesized, heavy viewers consumed alcohol significantly more often than did light and moderate viewers, especially the former, particularly when demographic variables were controlled simultaneously. Television as a powerful and pervasive influence on youth, containing many undesirable health messages, is discussed.  相似文献   
886.
Methylphenidate (Ritalin) has been shown to have differential effects on hyperactive children's behavior as a function of dose level. In the present investigation, a triple-blind, placebo-control, within-subject (crossover) experimental design was employed in which 12 hyperactive boys between 6 and 10 years received three different dosages of methylphenidate (5, 10, and 15 mg) in a randomly assigned sequence. Dosage effects were assessed on clinic(PAL-Paired Associates Learning test) and school-(percent on task, teacher ratings, work completion rates, and accuracy) related behaviors. For 10 of the children, classified as responders to medication by the PAL using the criteria of Swanson, Kinsbourne, and colleagues, a series of ANCOVAs with repeated measures showed significant dosage effects on teacher ratings (p 01), percent on task (p 01), academic accuracy (p 05), and assignment completion rates (p 05). PAL performance was also significantly enhanced (p 01) after optimal dose levels were considered. Subsequent trend analysis showed a significant positive linear relationship between dose and each of the dependent variables. A comparison of fixed-dose and miligram-per-kilogram plots showed that children's performance across the different dosages were clearly individualistic and task-specific, even when similar body weights were compared. The implications of using clinic-based testing to determine optimal medication responsivity were discussed.We would like to express our sincere appreciation to the following pediatricians for their valuable assistance: W. H. McDermott, D. J. Chronley, R. B. Trivett, F. J. Jehle, P. M. Small, and F. T. Leong. Grateful acknowledgement is also extended to the two anonymous reviewers whose comments contributed to the content of this paper, and to the undergraduate and graduate student members of the Children's Learning Clinic.  相似文献   
887.
Right-handed subjects were asked to decide whether or not faces presented briefly in the RVF or in the LVF were familiar (familiar faces were those of famous people). This task avoids the need for extensive semantic processing or temporary storage involved in conventional naming or identification tasks, and thus eliminates the contribution of such factors to any observed asymmetry. The resulting finding of faster reaction times to LVF faces, with no overall visual hemifield difference in error rates, is taken to indicate a right-hemisphere superiority either in the processes used to construct facial representations or in the accessing of face recognition units, or both.  相似文献   
888.
The authors identify and describe three major types of group therapy for patients with bulimia. Psychodynamic treatment, cognitive-behavioral treatment, and self-help group treatment are techniques with different theoretical bases. Implications for group membership, time frame, leadership, contract, content, and goals are discussed for each type of group treatment. Outcome studies are reviewed, and recommendations are offered for a rational approach to the group treatment of patients with bulimia.Supported in part by a grant from the Gen-Rad Foundation.  相似文献   
889.
Children (75 female, 52 male) in grades 2 through 8 completed the Fear Survey Schedule for Children (FSS-FC). Their mothers completed the same questionnaire twice: once for themselves and a second time to estimate their children's fears. Spearman's rhos indicated that there was a high degree of correspondence between the mothers' rank-ordered estimates of their children's fears and the children's rank-ordered self-reports (=.86 for males, =.96 for females.However, mothers' overall estimates of their children's general fearfulness were significantly correlated only with their daughters' fearfulness, not with their sons'. Further analyses showed that mothers could generally identify their children's highest-rated fears. All test-retest measures were significant. In summary, these results suggest that mothers may provide useful clinical information about their children's specific fears and that the FSS-FC is a reliable instrument with which to assess children's fears.  相似文献   
890.
A survey method was designed to evaluate the effect of shift work on industrial workers and to develop recommendations for 7-day around-the-clock production work systems. A Work-Sleep Survey was then offered to 2,340 hourly and salaried workers at four plants. Each plant was in the rubber and plastic products industry and on 5-day around-the-clock operations using permanent shifts. Of the total workers, 90.38% responded to the survey. The results agree with the findings of a previous survey, offered to workers through their unions, using many of the same survey items. The plants were found to differ in worker demographics, habits, and preferences. This survey method is helpful as an aid for the design and evaluation of shift-work systems tailored to specific worker and plant requirements.  相似文献   
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