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951.
952.
The relative effectiveness of incentive plans administered on continuous and VR-4 schedules of reinforcement was investigated with unionized employees using a within subjects design. Mountain beaver trappers working side by side were randomly assigned to one of two groups. In group A the trappers received $1.00 for every rat they trapped. At the end of four weeks, they were switched to a VR-4 schedule in which they received $4.00 contingent upon trapping a rat and correctly guessing the color of one of four marbles prior to drawing it from a bag held by the supervisor. In group B the order of the schedules was reversed. The results were analyzed in terms of cost-related, behavioral, and reaction criteria. The study increased employee productivity and decreased costs for the company. Inexperienced workers had higher productivity on the continuous reinforcement than on the VR-4 schedule; experienced workers had higher productivity on the VR-4 schedule than on the continuous schedule. Both the experienced and the inexperienced employees preferred the VR-4 schedule over the continuous schedule.  相似文献   
953.
Two reading passages, one with nasal consonants and one without, were tape-recorded for 72 subjects: 34 selected as having precise articulation and 38 selected as having imprecise articulation. These speech samples were evaluated for degree of precision and also for degree of nasality by the psychological scaling method of equal-appearing intervals employing a 7-point scale. Analysis indicated a relationship between degree of precision and degree of unpleasant nasality, that is, a tendency for decreases in precision to be accompanied by increased nasality and a tendency for males to be more imprecise in articulation and more nasal than females.  相似文献   
954.
A field study was conducted with 41 female typists in a large corporation to test an explanatory model of goal setting. Weekly productivity goals were either assigned by the supervisors or were set jointly with a typist. Goals were set for ten consecutive weeks. A correlational analysis of the data indicated that difficult goals led to higher performance. Higher performance led to higher absolute goals for the subsequent week, but smaller improvement goals. Persons with a high need for achievement and an internal control orientation set higher goals. Goal setting led to greater overall performance improvement for employees who had high self esteem or who perceived goal attainment to be instrumental for getting extrinsic rewards. Hypothesized relationships involving goal acceptance were not supported, which may have been due to a lack of validity for the goal acceptance measure.  相似文献   
955.
Preference for stimulus complexity across the life-span was investigated with 175 females ranging in age from 17 to 72 yr. of age. Preference for complexity appeared to be age-invariant and monotonic function. Relationships to previous findings are discussed.  相似文献   
956.
The possibility of using prerecorded words and 2-sec. delayed speech feedback as reinforcement in the reconditioning of intelligible verbal responses in a chronic, neologistic schizophrenic patient was investigated. A test situation was devised which involved daily presentation of 100 stimulus word-picture cards to elicit verbal responses. The results indicated that both singly presented prerecorded words and delayed speech feedback apparently strengthened correct and intelligible verbal responding.  相似文献   
957.
The fibrin(ogen) degradation product concentration is another differential-diagnosis parameter for distinguishing between artificially blood-stained and essentially blood-stained CSF. Determination of the fibrin(ogen) degradation product concentration has been found to be a reliable method of recognizing natively and artificially blood-stained CSF as being different.  相似文献   
958.
959.
Determinate solutions for the indeterminate common factor ofp variables satisfying the single common factor model are not unique. Therefore an infinite sequence of additional variables that conform jointly with the originalp variables to the original single common factor model does not determine a unique solution for the indeterminate factor of thep variables (although the solution is unique for the factor of the infinite sequence). Other infinite sequences may be found to determine different solutions for the factor of the originalp variables. The paper discusses a number of theorems about the effects of additional variables on factor indeterminacy in a model with a single common factor and draws conclusions from them for factor theory in general.  相似文献   
960.
In the applications of maximum likelihood factor analysis the occurrence of boundary minima instead of proper minima is no exception at all. In the past the causes of such improper solutions could not be detected. This was impossible because the matrices containing the parameters of the factor analysis model were kept positive definite. By dropping these constraints, it becomes possible to distinguish between the different causes of improper solutions. In this paper some of the most important causes are discussed and illustrated by means of artificial and empirical data.The author is indebted to H. J. Prins for stimulating and encouraging discussions.  相似文献   
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