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201.
GRADER, a computer program that makes student test and/or course letter grade recommendations to instructors, is described. The program uses an algorithm to combine the content mastery (percentage correct) and peer comparison (“curve”) approaches to set grade cutoffs. In addition to standardizing the procedures with which letter grade cutoffs are made, GRADER may help to reduce instructor grading subjectivity and obviate tendencies toward grade inflation or deflation.  相似文献   
202.
A running-wheel movement-detection method is described for use with a modified 1350 Commodore mouse and a Commodore 64, is described. The movement-detection method allows for the detection of partial revolutions and direction of movement, but requires no interface equipment. The modified running wheel is discussed as a new technique that may be useful for bridging empirical and theoretical differences between free-operant and discrete-trial runway procedures.  相似文献   
203.
Teams are playing an increasingly important role in the workplace. However, reviews of the team performance literature have suggested that there are serious deficiencies in our understanding of team processes and performance (e.g., Dyer, 1984). These difficulties may be attributable, in part, to the lack of laboratory methodologies to investigate team performance. This paper describes the use of low-fidelity simulations as a potentially useful paradigm for researching team coordination and performance. This paradigm is advantageous in that it offers relatively high levels of experimental control and task representation at a low cost.  相似文献   
204.
Millsap and Meredith (1988) have developed a generalization of principal components analysis for the simultaneous analysis of a number of variables observed in several populations or on several occasions. The algorithm they provide has some disadvantages. The present paper offers two alternating least squares algorithms for their method, suitable for small and large data sets, respectively. Lower and upper bounds are given for the loss function to be minimized in the Millsap and Meredith method. These can serve to indicate whether or not a global optimum for the simultaneous components analysis problem has been attained.Financial support by the Netherlands organization for scientific research (NWO) is gratefully acknowledged.  相似文献   
205.
A new method for determining the minimum number of observations per subject needed to achieve a specific generalizability coefficient is presented. This method, which consists of a branch-and-bound algorithm, allows for the employment of constraints specified by the investigator.  相似文献   
206.
Thirty adult male hooded rats (Long-Evans strain) were assigned randomly to one of three lesion groups (n = 10) and prepared with medial frontal, posterior parietal, or sham neocortical injuries. Following a recovery interval of 10-12 days, access to water was limited to 30 min per day and the rats were shaped to traverse a T-maze for a reward of sweetened water. After a pretraining criterion was attained, osmotic minipumps (Alzet 2002) were installed subcutaneously. The minipumps delivered chronically for the next 14 to 15 days either 0 or 1.2 micrograms of ACTH 4-9 dissolved in bacteriostatic saline per day while the rats were trained on a reinforced spatial alternation task. Analysis of the number of errors made to a criterion of at least 80% correct alternations in two consecutive training sessions, or a ceiling of 62 errors (attained by two rats with parietal lesions), revealed that learning was impaired in the rats with parietal injuries. Contrary to our hypothesis, animals receiving ACTH 4-9 committed more errors than their counterparts receiving only saline.  相似文献   
207.
This study investigated both an applicant pool and its resulting class of new hires in an attempt to clarify a number of empirical questions concerning recruiting source effectiveness. A pre-established database of applicants and hires for the job of life insurance agent in a large insurance company was analyzed for recruiting activity. Differences in applicant quality and new hire survival were found in favor of the informal recruiting sources. A second measure of hire success, new business commission credits, failed to show differences across recruiting sources. The informal recruiting sources yielded significantly higher selection ratios than did formal sources for all groups. Examination of recruiting source use showed significant group differences, with females and blacks using the formal recruiting sources more frequently than males, non-minorities, and Hispanics. While the informal recruiting sources yielded higher quality applicants and more successful hires for all groups, this research cautions that the implementation of revised recruiting policies must be carefully monitored for adverse effects on protected groups.  相似文献   
208.
209.
Trace mineral analysis of human hair was utilized to determine whether violent and nonviolent criminals could be differentiated on the basis of concentrations of levels of major and trace minerals. 40 violent and 40 nonviolent inmates from a prison population were selected for study. 27 mineral levels were analyzed and a discriminant function analysis correctly classified 86% of the violent and 78% of the nonviolent inmates. The results lent support to the hypothesis that significantly different levels of trace minerals could be found between the two groups.  相似文献   
210.
A case of episodic manifestation of semiparalysis agitans is described, accompanied by severe demential personality change and precursory hallucinatory symptoms, which is made the basis for the discussion of aspects of mental disorders, notably dementia and symptoms resembling schizophrenia, in Parkinsonian patients. By way of allusion to Glass, a diagnosis including a very extensive, complex, symptomatology is made of a Parkinsonian syndrome.  相似文献   
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