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111.
112.
Three experiments examining the information extraction processes are presented. In Experiments I and II, adults and children were presented paragraphs to read and search for specified targets, respectively. Two types of typographical (spatial) manipulations were used: case of the letters within the paragraphs was as normally experienced, or in alternating upper and lower case letters. Spacing between words was either as normal, filled with a neutral symbol, or absent. The response measures were reading and search speed in words per minute. Sensitivity to case (word shape) and space (word boundary) increased as a function of experience and was different for reading compared with search. In Experiment III subjects were asked to judge whether briefly presented pairs of letters were the same or different. Retinal (spatial) location was varied from trial to trial; dependent measure was reaction time. Results showed a developmental progression in response time with complex interactions. Theoretical interpretations of these data are discussed in support of the initial stage of Hochberg's peripheral to cognitive search guidance model.  相似文献   
113.
To investigate the development of verbal rehearsal strategies and selective attention in learning disabled children, Hagen's Central-Incidental task was administered to younger learning disabled (M CA = 8.68 years) and normal (M CA = 8.62 years) boys in Experiment 1 and to intermediate (M CA = 10.18 years) and older (M CA = 13.48 years) learning disabled boys in Experiment 2. Also, in Experiment 2, an experimentally induced verbal rehearsal condition was included to determine its effects on serial recall and selective attention performance. In Experiment 1, the serial postion curve of the normals revealed both a primacy and a recency effect, whereas that of the learning disabled revealed a recency effect only. In Experiment 2, both the intermediate and the older learning disabled exhibited both primacy and recency effects under both standard and rehearsal conditions. A developmental analysis of central recall for the three learning disabled groups revealed constant age-related increases in overall central recall and in primacy recall. That the normals recalled more central, but not more incidental, information than the learning disabled in Experiment 1 suggests that the learning disabled are deficient in selective attention. Correlational findings suggest that the selective attention of the learning disabled improves with age. The results were interpreted as support for the hypothesis of a developmental lag in the learning disabled population.  相似文献   
114.
Fitting and testing carroll's weighted unfolding model for preferences   总被引:1,自引:0,他引:1  
A quadratic programming algorithm is presented for fitting Carroll's weighted unfolding model for preferences to known multidimensional scale values. The algorithm can be applied directly to pairwise preferences; it permits nonnegativity constraints on subject weights; and it provides a means of testing various preference model hypotheses. While basically metric, it can be combined with Kruskal's monotone regression to fit ordinal data. Monte Carlo results show that (a) adequacy of true preference recovery depends on the number of data points and the amount of error, and (b) the proportion of data variance accounted for by the model sometimes only approximately reflects true recovery.This study is based on a doctoral dissertation submitted to the University of Illinois at Urbana-Champaign. The author wishes to thank the members of his dissertation committee—Lawrence E. Jones, Chairman, Charles Lewis, Stephen Golding, Ledyard Tucker, and Nancy Wiggins—for their helpful comments.  相似文献   
115.
It was suggested that thought changes cognitions to be more consistent with one's initial attitude direction and, therefore, results in attitude polarization. Specifically, it was predicted that polarization would be highest under thought with reality constraints absent, followed by thought with reality constraints present, followed by distration. During the first period of each of two trials, some of the 144 subjects were distracted from thinking about a preselected painting, others thought about the painting while viewing it, and others thought about it in its absence. Subjects were redistributed across the same three conditions for a second period. They then indicated their feelings about the painting. In the original study as well as a partial replication, females behaved as predicted: Thought with reality constraints absent produced the most polarization, followed by thought with reality constraints present, followed by distraction. In both the original study and the replication there was no systematic trend for the males. The theoretical implications of the female results and the sex differences were discussed.  相似文献   
116.
Using Louis’ formula, it is possible to obtain the observed information matrix and the corresponding large-sample standard error estimates after the expectation–maximization (EM) algorithm has converged. However, Louis’ formula is commonly de-emphasized due to its relatively complex integration representation, particularly when studying latent variable models. This paper provides a holistic overview that demonstrates how Louis’ formula can be applied efficiently to item response theory (IRT) models and other popular latent variable models, such as cognitive diagnostic models (CDMs). After presenting the algebraic components required for Louis’ formula, two real data analyses, with accompanying numerical illustrations, are presented. Next, a Monte Carlo simulation is presented to compare the computational efficiency of Louis’ formula with previously existing methods. Results from these presentations suggest that Louis’ formula should be adopted as a standard method when computing the observed information matrix for IRT models and CDMs fitted with the EM algorithm due to its computational efficiency and flexibility.  相似文献   
117.
Many studies indicate that increasing self-awareness leads to individuals reflecting on their values and ideals (Silvia & Duval, 2001). This self-reflection appears to increase prosocial behaviour (Berkowitz, 1987). However, previously studies typically manipulated self-awareness in situations in which the individual may have felt pressure from the researcher to help. Thus, experimenter pressure to behave prosocially confounds the self-awareness explanation provided in past research. We used a novel experimental paradigm to manipulate self-awareness and remove the researcher's presence to decrease the likelihood that the participant would conform to experimenter demand. Participants were 36 college students (Mage = 19.52; 25 women). The results indicated a strong probability that the experimental condition participants were more prosocial than control condition participants. These findings provide additional support for the hypothesis that self-reflection increases prosocial behaviour, even without experimenter demands. These findings and the importance of studying objective self-awareness in light of the coronavirus are discussed.  相似文献   
118.
In analyzing responses and response times to personality questionnaire items, models have been proposed which include the so-called “inverted-U effect.” These models predict that response times to personality test items decrease as the latent trait value of a given person gets closer to the attractiveness of an item. Initial studies into these models have focused on dichotomous personality items, and more recently, models for Likert-type scale items have been proposed. In all these models, it is assumed that the inverted-U effect is symmetrical around 0, while, as will be explained in this article, there are substantive and statistical reasons to study this assumption. Therefore, in this article, a general inverted-U model is proposed which accommodates two sources of asymmetry between the response times and the attractiveness of the items. The viability of this model is demonstrated in a simulation study, and the model is applied to the responses and response times of the Temperament and Character Inventory–Revised, covering a broad range of personality dimensions.  相似文献   
119.
Politicians are influential both in directing policies about refugees and in framing public discourse about them. However, unlike other host country residents, politicians' attitudes towards refugees and integration are remarkably understudied. We therefore examine similarities and differences between politicians' attitudes towards refugee integration and those held by citizens. Based on the stereotype content model, we expect that political ideology informs stereotypes about refugees, which subsequently shape attitudes towards refugee integration. Based on the Contact Hypothesis, we further argue that personal contact with refugees reduces negative stereotypes about them—in particular for those endorsing a right-wing ideology. We draw on data collected via two surveys with 905 politicians and 8013 citizens in the Netherlands to show that (1) unlike those with a left-wing orientation, residents (i.e., both politicians and citizens) with a right-wing orientation hold more negative stereotypes about refugees, which in turn relate to more negative attitudes towards refugee integration; (2) personal contact with refugees is associated with less negative stereotypes among residents; and (3) politicians, compared to citizens, report less negative stereotypes and more positive attitudes towards refugee integration. The practical implication of fostering residents' contact with refugees as well as the implications for future research are discussed.  相似文献   
120.
Behavioral activation (BA) is a well-established empirical treatment for depression that aims to improve depressive mood by increasing activation and reducing avoidance. Therefore, it is essential to evaluate activation and avoidance when a BA treatment is applied. The Behavioral Activation for Depression Scale (BADS) was developed to measure the changes in activation and avoidance over the course of BA treatment of depression. This study aims to validate the French version of this scale. In a first study, 131 bilingual adults were recruited to explored internal consistency, test-retest reliability and construct validity of the final French version. In a second study, 409 non-clinical adults completed an online survey assessing concurrent measures. Results of the first study suggested good internal consistency, test-retest reliability and construct validity. The second study revealed a confirmatory factor analysis supporting the original four-factor structure, with Activation, Avoidance/Rumination, Work/School Impairment, and Social Impairment subscales. Results also revealed that a 5-factor model distinguishing Behavioral Avoidance and Rumination had a better fit than the original four-factor structure. All subscales showed adequate internal consistency and good construct validity with evidence of convergent validity with depressive symptoms, brooding, psychological flexibility, negative automatic thought, behavioral inhibition and activation system. Furthermore, the French BADS total scale and subscales showed a good ability to predict depressive symptoms. The French version of the BADS appears to be a reliable tool for clinician and researchers to assess mechanisms of change in BA interventions.  相似文献   
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