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971.
In four experiments, subjects freely recalled previously studied items while a voice key and computer recorded each item’s recall latency relative to the onset of the recall period. The measures of recall probability and mean recall latency were shown to be empirically independent, demonstrating that there exists no a priori relationship between the two. In all four experiments, latency distributions were fit well by the ex-Gaussian, suggesting that retrieval includes a brief normally distributed initiation stage followed by a longer exponentially distributed search stage. Further, the variation in mean latency stemmed from the variation in the duration of the search stage, not the initiation stage. Interresponse times (IRTs), the time elapsed between two successive item recalls, were analyzed as well. The growth of mean IRTs, plotted as a function of output position, was shown to be a simple function of the number of items not yet recalled. Finally, the mathematical nature of both free recall latency and IRT growth are shown to be consistent with a simple theoretical account of retrieval that depicts mean recall latency as a measure of the breadth of search. 相似文献
972.
Robert F. Belli D. Stephen Lindsay Maria S. Gales Thomas T. McCarthy 《Memory & cognition》1994,22(1):40-54
The four experiments reported here provide evidence that (1) misleading postevent suggestions can impair memory for details in a witnessed event and (2) subjects sometimes remember sug-gested details as things seen in the event itself. All four experiments used recall tests in which subjects were warned of the possibility that the postevent information included misleading sug-gestions and were instructed to report both what they witnessed in the event and what was men-tioned in the postevent narrative. Recall of event details was poorer on misled items than on control items, and subjects sometimes misidentified the sources of their recollections. Our re-sults suggest that these findings are not due to guessing or response biases, but rather reflect genuine memory impairment and source monitoring confusions. 相似文献
973.
Subjects can name color words faster than they can name color patches. To account for that effect, a generic model of naming is described which assumes that words access the mental lexicon directly, whereas color patches do so only indirectly via an initial imaginal or semantic representation. However, Lund (1927) reported that the naming advantage for words disappeared when all the items to be named on a page were the same (i.e., they were blocked). In the present study, three experiments are reported that were designed to provide a clearer empirical definition of Lund’s blocking effect and to ascertain the extent to which it requires a modification of the generic model. The blocked lists had 50 items arranged into 10 blocks, with each block homogeneous with respect to color. The block lengths were either all a predictable length of 5 items or they varied randomly from 1 to 9 items. The data indicated the following: (1) The blocking effect occurred even when the task required a full identification of each item, and (2) the blocking effect was confined to within-block transitions. Blocking seemed to eliminate the word advantage by allowing the subject to re-use the lexical entry used for the immediately prior item, which is consistent with the generic model. 相似文献
974.
Introduction: Human Errors and Error Handling 总被引:1,自引:0,他引:1
975.
976.
Zellini (1979, Theorem 3.1) has shown how to decompose an arbitrary symmetric matrix of ordern ×n as a linear combination of 1/2n(n+1) fixed rank one matrices, thus constructing an explicit tensor basis for the set of symmetricn ×n matrices. Zellini's decomposition is based on properties of persymmetric matrices. In the present paper, a simplified tensor basis is given, by showing that a symmetric matrix can also be decomposed in terms of 1/2n(n+1) fixed binary matrices of rank one. The decomposition implies that ann ×n ×p array consisting ofp symmetricn ×n slabs has maximal rank 1/2n(n+1). Likewise, an unconstrained INDSCAL (symmetric CANDECOMP/PARAFAC) decomposition of such an array will yield a perfect fit in 1/2n(n+1) dimensions. When the fitting only pertains to the off-diagonal elements of the symmetric matrices, as is the case in a version of PARAFAC where communalities are involved, the maximal number of dimensions can be further reduced to 1/2n(n–1). However, when the saliences in INDSCAL are constrained to be nonnegative, the tensor basis result does not apply. In fact, it is shown that in this case the number of dimensions needed can be as large asp, the number of matrices analyzed. 相似文献
977.
T. E. Wilkerson 《Ratio》1994,7(2):164-182
Aristotle's account of akrasia is unsatisfactory for a number of reasons. First, his account of the problem is coloured by a number of unattractive assumptions and preoccupations; second, his central claim, that akrasia involves a temporary displacement of knowledge, deals at best with only a small number of cases; third, he is wrong to suppose that the akrates is typically someone overwhelmed by passion. We need to follow Davidson in recognising that the central problem consists in a failure to convert intention into action. Any solution must involve a recognition that we are dealing with a range of very different kinds of case, which demand different kinds of treatment. For example sometimes agents are overtaken by passion; sometimes they coolly and calmly do the wrong thing; sometimes they are insincere; sometimes they are suffering from a weakness of will; sometimes they are guilty of some kind of self deception; and sometimes they may have difficulty in comparing the goods and evils available. 相似文献
978.
Four homing pigeons were trained over 5 months in a zero-delay, “arbitrary” matching-to-sample procedure with sample and comparison stimuli presented on any of three response keys. Birds were also required to complete a fixed-ratio 10 requirement on both sample and comparison stimuli to terminate their presentation. The procedure resulted in the establishment of relations that were not specifically trained and that can be characterized by the property of transitivity in a stimulus equivalence context. This result was in contrast with the findings obtained from most previous research with nonhuman subjects. 相似文献
979.
M J Evans A Duvel M L Funk B Lehman J Sparrow N T Watson A Neuringer 《Journal of the experimental analysis of behavior》1994,62(1):149-156
An apparatus was developed to study social reinforcement in the rat. Four Long-Evans female rats were trained to press a lever via shaping, with the reinforcer being access to a castrated male rat. Responding under a fixed-ratio schedule and in extinction was also observed. Social access was found to be an effective reinforcer. When social reinforcement was compared with food reinforcement under similar conditions of deprivation and reinforcer duration, no significant differences were observed. 相似文献
980.
Four empirical studies of the roles of self-report questionnaires, tests, and ratings in employment interviews, staff appraisal,
and personnel validation surveys are presented in order to examine the number and relationships of psychological constructs
derived from data provided by candidates, employees, and their assessors. Test results are related to different kinds of criteria,
including job offers following interview, supervisor ratings on the job, and objective indices of work performance. From the
practices reported and observed in these various contexts, a theory of personal appraisal mechanisms in occupational settings
is derived using data reduction and linear regression methods. Applications of cognitive information processing theory to
self-reports and ratings by individuals, and of exchange theory to the social context of panel discussions among assessors,
provide a key to understanding why psychometric measures of personal qualities vary in their power to predict work performance
in spite of consistent construct validity. 相似文献