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991.
992.
Relational treatment of term graphs with bound variables 总被引:1,自引:0,他引:1
993.
We introduce two simple empirical approximate Bayes estimators (EABEs)—
and
—for estimating domain scores under binomial and hypergeometric distributions, respectively. Both EABEs (derived from corresponding marginal distributions of observed test scorex without relying on knowledge of prior domain score distributions) have been proven to hold -asymptotic optimality in Robbins' sense of convergence in mean. We found that, where
and
are the monotonized versions of
and
under Van Houwelingen's monotonization method, respectively, the convergence rate of the overall expected loss of Bayes risk in either
or
depends on test length, sample size, and ratio of test length to size of domain items. In terms of conditional Bayes risk,
and
outperform their maximum likelihood counterparts over the middle range of domain scales. In terms of mean-squared error, we also found that: (a) given a unimodal prior distribution of domain scores,
performs better than both
and a linear EBE of the beta-binomial model when domain item size is small or when test items reflect a high degree of heterogeneity; (b)
performs as well as
when prior distribution is bimodal and test items are homogeneous; and (c) the linear EBE is extremely robust when a large pool of homogeneous items plus a unimodal prior distribution exists.The authors are indebted to both anonymous reviewers, especially Reviewer 2, and the Editor for their invaluable comments and suggestions. Thanks are also due to Yuan-Chin Chang and Chin-Fu Hsiao for their help with our simulation and programming work. 相似文献
994.
Nikolaj Plotnikov 《Studies in East European Thought》1994,46(3):187-196
Lecturer in the Lomonossov University, Moscow, specialist in the young Hegel; has also worked quite extensively on Russian prerevolutionary thought. Nikolaj Plotnikov is notably the co-editor of the recently re-published texts,Vekhi, Iz Glubiny in the collection 'Iz istorii oteestvennoj filosofskoj mysli' in conjunction withVoprosy Filosofii. 相似文献
995.
996.
Florence Labrell 《Infant and child development》1994,3(2):125-130
The purpose of this article is threefold. First, it presents teasing behaviours towards the infant through the notion of ‘expectancy violation’, and defines what parental teasing may consist of. Secondly, the paper summarizes empirical data which show that teasing concerns more paternal than maternal behaviours. Thirdly, we speculate about a positive impact of this kind of typical paternal behaviour on cognitive and social development, as it introduces novelty and ambiguity, which must be processed, as well as negotiation of a struggle. 相似文献
997.
A. P. Grieve 《Psychometrika》1984,49(2):257-267
The locally best invariant test statistic for testing sphericity of normal distributions is shown to be a simple function of the Box/Geisser-Greenhouse degrees of freedom correction factor in a repeated measures design. Because of this relationship it provides a more intuitively appealing test of the necessary and sufficient conditions for valid F-tests in repeated measures analysis of variance than the likelihood ratio test. The properties of the two tests are compared and tables of the critical values of the Box/Geisser-Greenhouse correction factor are given. 相似文献
998.
Stimulus control, a behavioral technique designed to reduce sleep difficulties, has been demonstrated to be effective when compared with control procedures. These comparisons, mainly involving between-subjects analyses, have neglected the contribution of the stimulus control procedure to the production of clinically significant amelioration of sleep dysfunction. In contrast, the present within-subjects experiment was conducted to assess the capability of stimulus control to produce clinically relevant reductions in multiple measures of sleep disturbance. A comparison with the credible placebo procedure indicated that the stimulus control techniques reduced subjects' sleep onset latency to a mean latency below 30 min per week. Additionally, sedative-hypnotic usage was greatly reduced. 相似文献
999.
Rats discriminated auditory intensity differences of sinusoids at 3.0 kilohertz in a go/no-go signal detection procedure. Responses to the signal (hits) were reinforced with electrical brain stimulation, and misses produced a brief timeout. On intermixed noise trials, withholding of responses (correct rejections) was reinforced, and false alarms produced the time-out. In two test conditions, the signal was either the louder (100 decibels) or softer (90, 93, 96, or 99 decibels) of the pair of intensities presented within a set of trials. Each animal was first trained with signal value louder or softer, and reversed for the second condition so that the former noise value served as signal. Hits showed shorter latencies than false alarms, regardless of the relative intensity of signal and noise, and the magnitude of differentiation was proportional to signal-noise separation. Both hits and false alarms showed longer latencies as the discrimination became more difficult. Isosensitivity contours derived from the latencies showed close similarity across conditions; in comparison, the yes-no measure of detectability, d', showed greater variability. The similarity of latency differentiation across louder and softer signal conditions supports a detection model in which the observer's judgment is controlled by the distance of sensory effect from criterion on each trial, as opposed to the loudness of the tones per se. 相似文献
1000.