学习不良儿童社会性发展与家庭资源因果关系的研究

对普通学校2308名儿童中选取的211名学习不良儿童综合运用问卷测量和访谈等方法的结果表明,学习不良儿童社会性发展诸方面与家庭资源存在着相互作用。家庭资源影响学习不良儿童的社会性发展,家庭资源中的家庭心理环境、父母教养方式与学习不良儿童社会性发展诸方面具有一定的因果联系。对于学习不良儿童的教育矫正,家庭是一个不可忽视的重要因素。     

Tests for linear trend in the smallest eigenvalues of the correlation matrix

A test for linear trend among a set of eigenvalues of a correlation matrix is developed. As a technical implementation of Cattell's scree test, this is a generalization of Anderson's test for the equality of eigenvalues, and extends Bentler and Yuan's work on linear trends in eigenvalues of a covariance matrix. The power of minimumx ² and maximum likelihood ratio tests are compared. Examples show that the linear trend hypothesis is more realistic than the standard hypothesis of equality of eigenvalues, and that the hypothesis is compatible with standard decisions on the number of factors or components to retain in data analysis.This work was supported by National Institute on Drug Abuse Grants DA01070 and DA00017. The assistance of Maia Berkane and several anonymous reviewers is gratefully acknowledged.     

On the mean and variance of the tetrachoric correlation coefficient

Estimates of the mean and standard deviation of the tetrachoric correlation are compared with their expected values in several 2 × 2 tables. Significant bias in the mean is found when the minimum cell frequency is less than 5. Three formulas for the standard deviation are compared and guidelines given for their use.This research was performed when the first author was on leave at the University of California at Los Angeles and was supported in part by NIH Special Research Resources Grant RR-3. The second author was also supported by NIH Fellowship 5 F22 GM00328-02.     

On the relationship between the psychological environment and the development of individual differences in abilities

Some previous attempts at dimensionalizing human psychological environments are briefly considered. The problem is reformulated within the context of the development of dimensions of individual differences in abilities. The human psychological environment is viewed within the context of general systems theory. The latter permits an integrated view with respect to dimensions of the psychological environment and dimensions of individual differences within a developmental context. Critical in this formulation is the idea that, within the framework of the development of individual differences, it is of value to postulate the dimensions of the psychological environment as isomorphic to dimensions of individual differences.     

An identifiable model of two-stage learning

An eleven-parameter model for two-stage learning is developed. The model's principal advantage over extant two-stage models is that its parameter space is completely identifiable, thereby eliminating the tedious procedure of locating acceptable identifying restrictions. Identifiability is achieved by defining the model over a slightly modified outcome space. Following the identifiability proof, the necessary statistical machinery for parameter estimation, goodness-of-fit analyses, and hypothesis testing is presented. These latter developments are illustrated with data from an adult cued recall experiment and a free recall experiment with elementary school children.     

Prospective versus retrospective coding of samples of stimuli,responses, and reinforcers in delayed matching with pigeons

Pigeons' performance with samples of stimuli (red and green), number of responses (1 and 20), and reinforcers (food and no food) was assessed in a matching-to-sample preparation. Samples of red, 20 responses, and food were each associated with the red comparison stimulus; samples of green, 1 response, and no food were each associated with the green comparison stimulus. Interest focused on whether physically different samples associated with the same comparison stimulus each establish a unique memorial representation embodying the physical attributes of the sample (retrospective coding), or whether they activate a unitary memorial representation embodying an instruction for test responding (prospective coding). In the first experiment, accuracy of choice responding was independent of whether successive sample presentations within a trial involved the same physical sample or physically different but associatively identical samples. A second experiment revealed that, in contrast to other matching preparations, accuracy was not reduced when sample elements were compounded during presentation. It was concluded that physically different samples which are associated with the same comparison stimulus are coded prospectively in terms of an instruction for choice responding.     

Sequential response bias in randomized response sequences: A computer simulation

In this study sequential bias in randomized response sequences is simulated by computer. The computer model assumes that response bias is composed of two components. The first is a repetition avoidance tendency, which is simulated by a memory search through the seven most recently produced responses, and the second is a repetition tendency for the two most recently produced responses. This repetition tendency is assumed to be related to the better availability of recently produced responses. Both processes together give a reasonable approximation of human subjects' data.The results can be explained by the assumption that subjects try to control perseveration tendencies by using a comparison-based memory search mechanism.     

Voice onset time characteristics in apraxia of speech

In order to examine the timing control of laryngeal and supralaryngeal articulatory adjustments in apraxia of speech, voice onset time (VOT) data for stop consonants in monosyllables /de/, /te/, /ge/ and /ke/ were obtained from four apraxic subjects and compared with those of fluent aphasic and normal (both young and aged) speakers (Experiment 1). The results indicated that the VOT distribution patterns of the apraxic patients differed markedly from those of the other speakers. A second experiment was conducted to determine whether the VOT distribution patterns of these four apraxic patients and of two normal controls would change with a lapse of time (Experiment 2). The results of the second experiment demonstrated marked changes in the VOT distribution patterns over time in half of the apraxic patients examined, but essentially no change in the normal controls.     

No impairment in sign language after right-hemisphere stroke

A 52-year-old right-handed woman who became deaf before the development of speech, suffered an occlusion of the right middle cerebral and a marked stenosis of the right anterior cerebral arteries. She showed no disturbance in the manual sign language or in finger-spelling, in contrast to previous reports of cases with left-sided damage.     

Affiliativeness: A trait measure in relation to single-act and multiple-act behavioral criteria

The validity of trait affiliativeness is examined. Based on an assertion related to attitudes, it was predicted that a trait measure would predict a single-act criterion worst, a repeated measure of a single act better, and a multiple-act criterion best. The prediction was confirmed, supporting the notion that traits are, as originally conceived, good predictors of broadly based behavioral tendencies but not necessarily of isolated acts.