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21.
Ordinal data occur frequently in the social sciences. When applying principal component analysis (PCA), however, those data are often treated as numeric, implying linear relationships between the variables at hand; alternatively, non-linear PCA is applied where the obtained quantifications are sometimes hard to interpret. Non-linear PCA for categorical data, also called optimal scoring/scaling, constructs new variables by assigning numerical values to categories such that the proportion of variance in those new variables that is explained by a predefined number of principal components (PCs) is maximized. We propose a penalized version of non-linear PCA for ordinal variables that is a smoothed intermediate between standard PCA on category labels and non-linear PCA as used so far. The new approach is by no means limited to monotonic effects and offers both better interpretability of the non-linear transformation of the category labels and better performance on validation data than unpenalized non-linear PCA and/or standard linear PCA. In particular, an application of penalized optimal scaling to ordinal data as given with the International Classification of Functioning, Disability and Health (ICF) is provided.  相似文献   
22.
L'A. fait L'hypothèse que le dédoublement de la représentation, qui est caractéristique du style graphique de certaines cultures, provient d'une préférence universelle pour ce type de dessin chez les tout jeunes enfants de toutes cultures; mais dans la plupart des cultures, cette préférence serait supprimée parce que, paradoxalement, les dessins doubles ne permettent pas de reconnaître les objets dessinés aussi facilement que les dessins conventionnels qui sont plus proches de la projection rétinienne des objets. Les dessins avec enchaînement ou dédoublement de la représentation seraient conservés chaque fois qu'ils sont appréciés en tant que code utilisé à d'autres fins que L'information sur les objets peints et pour leur valeur esthétique.  相似文献   
23.
Procedures for determining logicality presuppose understanding, and procedures for determining understanding presuppose logic. One can escape from this circle only by presupposing logicality, in agreement with common-sense thinking. Understanding can then be studied as an empirical variable. Traditional research has been based on the opposite solution: Logicality is treated as an empirical variable, understanding is implicitly presupposed; hence results are obtained which do not 'make sense'. One cannot understand the illogical.  相似文献   
24.
Two groups of children, median ages 6–7 and 8–7, were presented with objects examplifying three combinations of two dichotomous attributes, and asked to indicate the remaining combination. Keeping objects covered vs. uncovered at the time of the test response had generally little effect. Labelling was consistently superior to perceptual matching, apparently because the latter involved a search process. The errors in the labelling condition consisted mostly in naming an object identical to or different in both attributes from those given, reflecting perhaps an inability to break down the impression of the objects into independent attributes.  相似文献   
25.
We used quadratic shapes in several psychophysical shape-from-stereo tasks. The shapes were elegantly represented in a 2-D parameter space by the scale-independentshape index and the scale-dependentcurvedness. Using random-dot stereograms to depict the surfaces, we found that the shape of hyperbolic surfaces is slightly more difficult to recognize than the shape of elliptic surfaces. We found that curvedness (and indirectly, scale) has little or no influence on shape recognition.  相似文献   
26.
The present research focused on power processes in a simulated organizational structure consisting of three hierarchical levels occupied by different numbers of mules and females. Subjects were presented with a chart showing the organizational hierarchy of which they were a member placed at the lowest level, and asked to nominate any person for the leader position vacated by the current incumbent. The results of Experiment I (n = 88 Dutch male and female university students) showed that male subjects strongly overnominated themselves, whereas a majority of the female subjects nominated either self or another female. Of the others that were nominated by both males and females, almost all were occupants of positions immediately below the leader position, indicating the normative influence of a bureaucratic rule of leader succession. Experiment 2 was a replicational study carried out in a different culture (n = lOl Polish male and female university students). Polish subjects adhered to the bureaucratic rule more strongly than their Dutch counterparts, and both females and males nominated mostly males. Results are discussed with reference to gender self-stereotypes and cultural differences.  相似文献   
27.
An experiment was conducted to examine the influence of the perceived extremity of a message and motivation to elaborate upon the process of persuasion. The first goal was to test a model of attitude change relating Social Judgment Theory to the Elaboration Likelihood Model. The second objective was to develop an instrument to measure attitude structure (latitudes of acceptance, non-commitment, and rejection) that allowed for a more refined assessment of the discrepancy between the position advocated in a message and the recipient's initial attitude. The main dependent variable was the attitude towards the use of automobiles in relation to environmental issues. Subjects were confronted with a message located in their own latitude of acceptance, rejection or non-commitment. Shortly after, a second measurement of attitude took place. The results showed that messages within the latitudes of non-commitment gave rise to the greatest attitude change. The data support the susceptibility hypothesis that subjects elaborate messages mainly in the latitude of non-commitment.  相似文献   
28.
Expert research administrators responded to questions to determine to what degree they had postformal thinking skills. Postformal theory suggests that the interpersonal and institutional complexity of work roles would make them likely to exhibit postformal thought. The tests included a questionnaire about the use of postformal operations on the job, and thinking-aloud taped interviews of responses to job-related and standard postformal problems. The respondents demonstrated the use of postformal thinking operations on job-related tests and a more moderate degree of use on the standard problems. The results support prior research and our working hypothesis that a high degree of interaction with people and complex problems is associated with adults' postformal thought.  相似文献   
29.
The question asked in this study of 70 clinically referred 6- to 12-year-old boys with behavior problems was whether or not childhood inattention-overactivity and aggression are transmitted specifically from biological fathers to sons. Fathers' self-reported childhood inattention-overactivity on a retrospectively valid measure was exclusively associated with parents' ratings of their sons' current attention problems on the Mothers' Operational Measure for Sub-grouping (MOMS), the Revised Child Behavior Checklist (RCBCL), and an approximated DSM-IV inattention dimension. Fathers' self-reported childhood aggression was not associated with ratings of their sons' aggression on the MOMS or DADS (a parallel instrument for fathers), nor on DSM-III oppositional or conduct disorder dimensions, but it was exclusively associated with RCBCL ratings of sons' aggressive and delinquent behavior. None of the nonspecific correlations (father inattention-overactivity with son aggression or father aggression with son inattention-overactivity) was significant.  相似文献   
30.
Collaborative recall in episodic memory tasks was investigated in two experiments. The experiments were explicitly designed to investigate how the interaction between two subjects influences group productivity. Subjects were requested to recall twice, first individually, and second, in different subject constellations (individually, or in dyads, as friends or non-friends). Experiment 1 employed free recall of words and story recall. In Experiment 2, a video-taped lecture on child development was recalled. The observed score at the second recall (Recall 2) was compared with the nominal predicted score, based on the initial recall. The results of the experiments are summarized and discussed in four clusters: (1) observed productivity for dyads never reached their predicted potential; (2) the negative effects of collaborative recall can be reduced; (3) friends rather than non-friends, and complex rather than simple tasks, reduce the loss in productivity; and (4) the data also suggest that encoding alone is superior to collaborative encoding.  相似文献   
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