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Time series analysis was used to investigate the hypothesis that during acquisition of a motor skill, knowledge of results (KR) information is used to generate a stable internal referent about which response errors are randomly distributed. Sixteen subjects completed 50 acquisition trials of each of three movements whose spatial-temporal characteristics differed. Acquisition trials were either blocked, with each movement being presented in series, or randomized, with the presentation of movements occurring in random order. Analysis of movement time data indicated the contextual interference effect reported in previous studies was replicated in the present experiment. Time series analysis of the acquisition trial data revealed the majority of individual subject response patterns during blocked trials were best described by a model with a temporarily stationary, internal reference of the criterion and systematic, trial-to-trial variation of response errors. During random trial conditions, response patterns were usually best described by a "White-noise" model. This model predicts a permanently stationary, internal reference associated with randomly distributed response errors that are unaffected by KR information. These results are not consistent with previous work using time series analysis to describe motor behavior (Spray & Newell, 1986). 相似文献
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Brazin LR 《Medical reference services quarterly》1993,12(3):13-27
This is an update of an earlier article listing directories, journal articles, and general books that aid the librarian, resident, or medical student in finding information on residency and fellowship programs. The article also gives suggestions for building a file of program catalogs related to residencies, fellowships, and clerkships and related materials. 相似文献
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In order to assess the current status of MEDLINE training provided by schools of library science, a survey was conducted of those schools having an educational identification code issued by the National Library of Medicine. Information was gathered on such variables as the instructors' background and preparation, the course objectives and content, and the amount of on-line experience provided to students in each of eleven programs. An evaluation of these measures indicates that more opportunities to gain experience in using MEDLINE should be initiated by library schools and that current efforts should be continued and expanded. Specific recommendations for accomplishing these goals are outlined; they are addressed to health sciences librarians, library school educators, the Medical Library Association, and the National Library of Medicine. 相似文献