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121.
A community education program, to develop a variety of performance competencies in large numbers of neighborhood residents, requires a technology for preparing learning units administerable by community members themselves. The effects of a writing manual, designed to teach nonprofessionals to prepare such instructional packages, were analyzed in two experiments. Experiment I employed a multiple-baseline design across three university student trainees. The results showed that appropriate program writing increased by 75% after completion of the manual. The results of Experiment II, with two low-income neighborhood residents serving as trainees, showed that packages produced by trained writers resulted in a greater increase in skill activities than sets of training stimuli produced by untrained writers.  相似文献   
122.
Time-series analysis in operant research   总被引:1,自引:0,他引:1  
A time-series method is presented, nontechnically, for analysis of data generated in individual-subject operant studies, and is recommended as a supplement to visual analysis of behavior change in reversal or multiple-baseline experiments. The method can be used to identify three kinds of statistically significant behavior change: (a) changes in score levels from one experimental phase to another, (b) reliable upward or downward trends in scores, and (c) changes in trends between phases. The detection of, and reliance on, serial dependency (autocorrelation among temporally adjacent scores) in individual-subject behavioral scores is emphasized. Examples of published data from the operant literature are used to illustrate the time-series method.  相似文献   
123.
Human altruistic responding (called give responding), which delivered a reinforcer to someone other than the responder, was compared to responding where the responder was the recipient of the reinforcer (called earn responding). The same type of response (button pressing), the same reinforcer (a point representing a penny), and the same reinforcer contingency (a 40-response fixed-ratio schedule) were used for both give and earn responding. Since points representing pennies were used to reinforce give and earn responding, responding for points not worth money was also assessed. Give, earn, and point responding were arranged as concurrent incompatible operants. Lowest rates were obtained for point responding. Compared to earn responding, give responding occurred at lower rates, was more susceptible to cessation when point responding was possible, extinguished more rapidly in the absence of money, and produced less responding during reconditioning compared to conditioning when reconditioning followed a period of nonreinforcement. Give responding was less when it reduced the giver's opportunity to earn. Finally, histories of getting reinforcement from others were shown to determine give responding.  相似文献   
124.
Tucker has outlined an application of principal components analysis to a set of learning curves, for the purpose of identifying meaningful dimensions of individual differences in learning tasks. Since the principal components are defined in terms of a statistical criterion (maximum variance accounted for) rather than a substantive one, it is typically desirable to rotate the components to a more interpretable orientation. Simple structure is not a particularly appealing consideration for such a rotation; it is more reasonable to believe that any meaningful factor should form a (locally) smooth curve when the component loadings are plotted against trial number. Accordingly, this paper develops a procedure for transforming an arbitrary set of component reference curves to a new set which are mutually orthogonal and, subject to orthogonality, are as smooth as possible in a well defined (least squares) sense. Potential applications to learning data, electrophysiological responses, and growth data are indicated.Portions of this research were supported by the National Research Council of Canada, Grant A8615 to the second author. We thank Jagdeth Sheth for supplying his raw data.  相似文献   
125.
A two-step weighted least squares estimator for multiple factor analysis of dichotomized variables is discussed. The estimator is based on the first and second order joint probabilities. Asymptotic standard errors and a model test are obtained by applying the Jackknife procedure.  相似文献   
126.
The use of conversation-related skills by youthful offenders can influence social interactions with adults. These behaviors are also likely to be useful to adolescents after their release from a treatment program (Journal of Applied Behavior Analysis, 1972, 5 , 343–372). Four girls, aged 13 to 15 yr, residing at Achievement Place for Girls in Lawrence, Kansas, received training on conversation-related behaviors. A multiple-baseline design across youths and across behaviors was used. Youth answer-volunteering in response to questions and three youth nonverbal components (“hand on face”, “hand at rest”, and “facial orientation”) were measured during daily 10-min sessions with a simulated guest in the group home's living room. Answer-volunteering was scored each session as the per cent of 13 “secondary” questions that the simulated guest did not have to ask following 10 “primary” questions. The three nonverbal components were scored according to their occurrence during 10-sec intervals and the resultant scores were averaged per session for an overall appropriate nonverbal score. The girls individually earned points within the home's token economy for participating in each session and additional points were awarded after training if preselected behavioral criteria were achieved for each of the two behavior categories per girl. Some of the training sessions were led by a “teaching-parent” (specially trained houseparent) while others were led by individual girls. Point consequences were administered by both the teaching-parent and by the “peer-trainers”. The average observed rate of answer-volunteering by the girls during pretraining sessions was 30% for S1, 30% for S2, 23% for S3, and 68% for S4. The average rate of answer-volunteering during posttraining sessions was: S1 = 92%, S2 = 89%, S3 = 90%, and S4 = 98%. The average nonverbal score during pretraining sessions was 82% for S1, 53% for S2, 60% for S3, and 82% for S4. The average nonverbal score during posttraining sessions was: S1 = 98%, S2 = 98%, S3 = 98%, and S4 = 100%. Videotapes of the sessions were shown in a random sequence to four adults (probation officer, social worker, etc who represented “significant others” for the youths' future success in the community. The adults judged posttraining tapes on the average as more appropriate 100% of the time for S1, 100% of the time for S2, 90% of the time for S3, and 70% of the time for S4. The study demonstrated that training of conversation-related skills is feasible with predelinquent girls, that the girls can help train each other, and that social validation of the training results is possible.  相似文献   
127.
Failure to share household chores equitably may be a major cause of the high failure rate of experimental group-living arrangements. A behavioral approach to worksharing based on a point system was implemented in one experimental group and its most important components experimentally evaluated. Experiment I showed that awarding credits produced more work than not awarding credits. Experiment II showed that making credits contingent on the outcome of a detailed inspection produced more work than awarding credits noncontingently. Experiment III demonstrated that awarding rent reductions contingent on credit earnings produced more work than awarding rent reductions noncontingently. Other evaluative data suggest that the resulting living arrangement is cheaper, more effective, and more satisfactory to the residents when compared to the most popular alternative living arrangements.  相似文献   
128.
In order to make the parallel analysis criterion for determining the number of factors easy to use, regression equations for predicting the logarithms of the latent roots of random correlation matrices, with squared multiple correlations on the diagonal, are presented. The correlation matrices were derived from distributions of normally distributed random numbers. The independent variables are log (N–1) and log {[n(n–1)/2]–[(i–1)n]}, whereN is the number of observations;n, the number of variables; andi, the ordinal position of the eigenvalue. The results were excellent, with multiple correlation coefficients ranging from .9948 to .9992.This research was supported by the Office of Naval Research under Contract N00014-67-A-0305-0012, Lloyd G. Humphreys, principal investigator, and by the Department of Computer Science of which Richard G. Montanelli, Jr., is a member.  相似文献   
129.
130.
Guttman's index of indeterminacy (22 – 1) measures the potential amount of uncertainty in picking the right alternative interpretation for a factor. When alternative solutions for a factor are equally likely to be correct, then the squared multiple correlation 2 for predicting the factor from the observed variables is the average correlation AB between independently selected alternative solutionsA andB, while var ( AB )=(1 – 2)2/s, wheres is the dimensionality of the space in which unpredicted components of alternative solutions are to be found. When alternative solutions for the factor are not equally likely to be chosen, 2 is the lower bound for E( AB ); however, E( AB ) need not be a modal value in the distribution of AB . Guttman's index and E( AB ) measure different aspects of the same indeterminacy problem.  相似文献   
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