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861.
The cyclic variation in the energy envelope of the speech signal results from the production of speech in syllables. This acoustic property is often identified as a source of information in the perception of syllable attributes, though spectral variation can also provide this information reliably. In the present study of the relative contributions of the energy and spectral envelopes in speech perception, we employed sinusoidal replicas of utterances, which permitted us to examine the roles of these acoustic properties in establishing or maintaining time-varying perceptual coherence. Three experiments were carried out to assess the independent perceptual effects of variation in sinusoidal amplitude and frequency, using sentence-length signals. In Experiment 1, we found that the fine grain of amplitude variation was not necessary for the perception of segmental and suprasegmental linguistic attributes; in Experiment 2, we found that amplitude was nonetheless effective in influencing syllable perception, and that in some circumstances it was crucial to segmental perception; in Experiment 3, we observed that coarse-grain amplitude variation, above all, proved to be extremely important in phonetic perception. We conclude that in perceiving sinusoidal replicas, the perceiver derives much from following the coherent pattern of frequency variation and gross signal energy, but probably derives rather little from tracking the precise details of the energy envelope. These findings encourage the view that the perceiver uses time-varying acoustic properties selectively in understanding speech. 相似文献
862.
P A Beckett 《Perceptual and motor skills》1990,70(1):51-56
Measures of illusion magnitude for a real-contour and two subjective-contour Poggendorff figures were obtained from 42 men and 42 women. Although magnitudes of illusion differed as a function of figure type, male-female differences in magnitude of illusion did not vary across figures or judgment orders. Also, correlations among the illusions observed for three types of figures did not differ for men and women. These data are consistent with the view that real- and subjective-contour Poggendorff figures evoke similar processing strategies and that sex differences, when observed, are probably the result of differences in cognitive-judgmental strategy rather than differences in the optical and neural properties of the visual system. 相似文献
863.
This study is a systematic replication of the effects of insulin doses on operant behavior reinforced (in an earlier study) by fixed-ratio schedules of microwave (MW) reinforcement. In this study, insulin and dextrose doses were administered (ip) prior to fixed-interval 2-min. schedules of MW reinforcement in rats tested in a cold environment. Six Sprague-Dawley rats were conditioned to regulate their thermal environment with 5-sec. exposures of MW radiation (SAR = 0.34 Watts/kg/(mW/cm2) under the FI-2' schedules. Humulin-regular insulin and 50% solutions of dextrose were administered (ip) alternately with saline control sessions for 8-hr. durations. A within-subjects, repeated-measures 4 x 8 x 3 factorial analysis of variance design showed that insulin doses suppressed operant responding for heat, which confirmed the results of the earlier study under a different schedule. In addition, high doses of dextrose had similar suppressing effects on operant responding for heat. The data are interpreted in terms of the discriminative properties of increased thermogenesis produced by the insulin and dextrose doses. The suppressing effects were more pronounced for the first two hours, yet they persisted for approximately six hours of the 8-hr. sessions. 相似文献
864.
RELIABILITY AND VALIDITY OF IN-BASKET PERFORMANCE MEASURES 总被引:2,自引:0,他引:2
The in-basket test is a frequently used assessment tool for predicting job performance and, to a lesser extent, as a technique for research and development in various human resource applications. While the in-basket test has obvious attractive features for application in the business setting, there is a great degree of uniqueness in each application and relatively little research focusing on critical issues involved in construction or evaluation. In this paper, the literature focusing on the psychometric properties of in-basket measures of performance are reviewed and evaluated. The compiled evidence provides only modest support of the usefulness of the in-basket test as a measurement tool. 相似文献
865.
ROBERT SADACCA JOHN P. CAMPBELL ANIS. DIFAZIO SHEILA R. SCHULTZ LEONARD A. WHITE 《Personnel Psychology》1990,43(2):367-378
For purposes of selection and classification there are two general reasons for scaling the mean and variance of the utility of performance across jobs. First, if differential utility across jobs does exist, then the payoff from a selection and classification system will be enhanced to the extent that accurate utility values are incorporated in the assignment system. Second, a valid utility metric would permit a more meaningful comparison of the gains achieved by alternative selection and classification procedures. It is argued in this paper that the Army context, and perhaps others, precludes using the dollar metric and estimates of SDy in dollars. Consequently, Project A conducted a relatively long series of exploratory workshops with Army personnel to (a) define the utility issue, (b) pilot test a wide variety of possible scaling methods, and (c) evaluate the methods that seemed most appropriate. On the basis of exploratory analysis, a combined procedure incorporating both an interval estimation and a ratio estimation method was used to estimate the utility of five different performance levels for each of 276 jobs (MOS) in the enlisted personnel system. The psychometric properties of the resulting scale values are analyzed and discussed. 相似文献
866.
MODELING JOB PERFORMANCE IN A POPULATION OF JOBS 总被引:9,自引:0,他引:9
The Army Selection and Classification Project has produced a comprehensive examination of job performance in 19 entry-level Army jobs (Military Occupational Specialties) sampled from the existing population of entry-level positions. Multiple methods of job analysis and criterion measurement were utilized in a subsample of nine jobs to generate over 200 performance indicators, which were then used to assess performance in a combined sample of 9,430 job incumbents. An iterative procedure involving a series of content analyses and principal components analyses was used to develop a basic array of up to 32 criterion scores for each job. This basic set of scores formed the starting point of an attempt to model the latent structure of performance in this population of jobs. After alternative models were proposed for the latent structure, the models were submitted to a goodness-of-fit test via LIS-REL VI. After accounting for two components of method variance, a five-factor solution was judged as the best fit. The implications of the results and the modeling procedure for future personnel research are discussed. 相似文献
867.
Two studies examined the speed with which good spellers and poor spellers spell easy and difficult words. At both the elementary school (Grades 3 and 4) and undergraduate levels, good spellers spelled words more quickly than poor spellers. This difference appeared even for very easy words that all subjects could spell. Implications for the importance of automaticity in spelling competence are discussed. 相似文献
868.
This study was based on data from a longitudinal research program. The cohort consisted of 874 normal children in an entire school grade in a Swedish community. The aim of the study was to investigate the relation between birth weight and behavior at school, for all children and for each sex separately. The results identified specific aspects of behaviour disorder significantly related to low birth weight (LBW) for children at the age of 10 but not at the age of 13. When the sexes were separated, there were no relations between birth weight and deviant behaviour for boys of low birth weight as compared to boys of normal birth weight, while girls of low birth weight showed specific behavioural disorders at age 10 as compared to girls of normal birth weight. For girls reared in families of low parental socioeconomic status, aggressiveness and motor restlessness at age 10 but not at age 13 was also present. Further analyses showed that girls born small-for-gestational age showed lack of school motivation and concentration difficulties both at age 10 and age 13. 相似文献
869.
John L. Pollock 《Philosophical Studies》1990,58(1-2):95-120
Conclusions To conclude then, our question was, What determines the content of a thought? This question gets its punch by being set against the background assumption that thoughts are internal physical occurrences. The answer I have proposed is that thoughts can be classified in four importantly different ways. Introspection yields syntactic categories. These are important for cognitive processing, but they do not correspond to contents. A second way of categorizing thoughts is in terms of narrow content. This is determined by the functional role of the thought in rational architecture together with the way in which that rational architecture is tied to the world through input correlations. Narrow contents are indexical, so to get truth bearers we must augment the narrow contents with the values of the indexical parameters. Propositional content can be taken to consist of pairs of narrow contents and values for indexical parameters. Finally, thoughts can be classified in terms of that clauses. This kind of classification does not uniquely determine propositional content, but describes it in a more general way. 相似文献
870.
G Mladek M L?ffler P Nickel 《Psychiatrie, Neurologie, und medizinische Psychologie》1990,42(6):356-363
In forensic psychology, recommendations that courts request when granting one of the parents the right of child upbringing after a divorce pose a problem for the person who is required to give such expert judgment. The authors describe the difficult situation he faces when having to decide for and, at the same time, against one of the parents. A good knowledge of family psychology and pathopsychology is essential, and for drawing up the expertise and stating his reasons, the expert requires methodical resources. The authors describe four procedures of relational diagnosis and recommend the combined use of these in conjunction with methods that have been employed so far. 相似文献