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151.
Within the framework of valence-instrumentality (VI) theory, a fourfold model is developed to predict the contribution which is made by one outcome of an alternative to the valence of that alternative. The proposed model uses four subjective conditional probabilities which are based on the presence and absence of an alternative, and on the occurrence and nonoccurrence of an outcome. Valence is defined as the difference between the attractiveness values of the occurrence of an alternative (or an outcome) and the nonoccurrence of an alternative (or an outcome). Also, differences between subjective probabilities replace instrumentalities. Alternative valence-instrumentality formulations are analyzed in relation to the proposed fourfold model. The proposed model can be understood as a consistent application of Vroom's model (1964, Work and motivation, New York: Wiley), while other models are judged to be relatively deficient. The fourfold model, in combination with a matrix formulation of expectancy concepts, addresses a number of criticisms of VI theory and makes possible a test of the theory within the limits of its own assumptions.  相似文献   
152.
This paper demonstrates a method of transferring research data from a remote clinic to a large university mainframe for data manipulation and statistical analysis. Data collected by an Apple //e computer were transferred to an IBM 3031 mainframe by sending data files to an IBM PC by telephone modem or by direct hardwire connection to the PC. The IMB PC performed data-formatting routines and then uploaded the files to the mainframe for storage. Advantages and disadvantages of sending data over telephone lines via a modem are discussed.  相似文献   
153.
Blind readers were tested using two methods of reading text displayed by an Apple microcomputer. The first method employed an Optacon system, a device that displays tactile representations of single characters, and the second used an interactive single electronic braille cell that displayed grade 1 braille characters. The results demonstrated no difference in accuracy or reading speed between these two methods. Thus, the serial presentation of braille characters at a single position appears to be a viable method of information transfer between computers and braille readers.  相似文献   
154.
Single-subject statistics were used to analyze physiological data [electromyographic (EMG) temperature] recorded from two patients receiving computer-assisted biofeedback treatment in a clinic. When the data were analyzed by an ANOVA method or a regression technique, the results demonstrated that both patients learned to significantly reduce EMG levels. The rationale of using single-subject statistics is discussed, and the applicability of the statistical technique to the clinic population is illustrated.  相似文献   
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157.
Cadets at the U.S. Military Academy completed a questionnaire describing their experiences in Cadet Basic Training (CBT) and Cadet Field Training (CFT). Analyses of variance examined the impact of Group Role (Leader vs. Follower) and Perceived Group Effectiveness (High vs. Low) on group member perceptions of the extent to which each of six factors affected group performance. Significant main effects for Perceived Effectiveness were interpreted in terms of the egodefensive bias. Role main effects indicated that leaders tended to make stronger dispositional attributions than did followers. There were no signifcant Group Role × Perceived Effectiveness interaction effects. Findings support, in part, hypotheses concerning the operation of an attributional bias within the leader-member relationship.  相似文献   
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159.
Against the background claims that a meaningful life is more likely to be the product of creation than discovery and that a meaningful life must involve both subjective satisfaction and an objective moral component, three foundations of a meaningful life are discussed. These include the quality of one's relationships, the integrative power of one's goals and projects, and the role of story or stories. Concerning the role of story, the theological challenge is to choose that story or those stories that place life in a genuinely ultimate context.  相似文献   
160.
Six pigeons were exposed to concurrent variable-interval schedules in which the programmed reinforcer ratios changed from session to session according to a pseudorandom binary sequence. This procedure corresponded to the stochastic identification paradigm (“white-noise experiment”) of systems theory and enabled the relation between log response ratios in the current session and log reinforcer ratios in all previous sessions to be determined. Such dynamic relations are called linear transfer functions. Both nonparametric and parametric representations of these, in the form of “impulse-response functions,” were determined for each bird. The session-to-session response ratios resulting from the session-to-session pseudorandom binary variations in reinforcer ratios were well predicted by the impulse-response functions identified for each pigeon. The impulse-response functions were well fitted by a second-order dynamic model involving only two parameters: a time constant and a gain. The mean time constant was 0.67 sessions, implying that the effects of abrupt changes in log reinforcer ratios should be 96% complete within about five sessions. The mean gain was 0.53, which was surprisingly low inasmuch as it should equal the sensitivity to reinforcement ratio observed under steady-state conditions. The same six pigeons were subjected to a similar experiment 10 months following the first. Despite individual differences in impulse-response functions between birds within each experiment, the impulse-response functions determined from the two experiments were essentially the same.  相似文献   
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