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991.
This article concerns acceptance of the null hypothesis that one variable has no effect on another. Despite frequent opinions to the contrary, this null hypothesis can be correct in some situations. Appropriate criteria for accepting the null hypothesis are (1) that the null hypothesis is possible; (2) that the results are consistent with the null hypothesis; and (3) that the experiment was a good effort to find an effect. These criteria are consistent with the meta-rules for psychology. The good-effort criterion is subjective, which is somewhat undesirable, but the alternative—never accepting the null hypothesis—is neither desirable nor practical.  相似文献   
992.
Biased attention in childhood Anxiety disorders: A preliminary study   总被引:7,自引:0,他引:7  
This study provides preliminary tests of two hypotheses: (1) Anxiety-disordered children show an attentional bias toward emotionally threatening stimuli, and (2) normal controls show an attentional bias away from emotionally threatening stimuli. Twelve children, 9 to 14 years of age, with primary diagnoses of anxiety disorder were compared with 12 normal controls matched for age, gender, vocabulary level, and reading ability. Subjects completed a reaction time task that measured visual attention toward threatening versus neutral words. The anxious group showed the predicted attentional bias toward threat words. However, controls did not show the predicted bias away from threat words. These results are the first showing that biased attentional processing occurs among clinically anxious children. The potential role of such an attentional bias in childhood anxiety disorders and future direction for research are discussed.This research was supported by a Seed Grant and a Small Grant to the first author from The Ohio State University. Portions of this paper were presented at the 27th Annual Convention of the Association for the Advancement of Behavior Therapy, Atlanta, November 1993. Thanks are extended to the participants and all those who helped with the project.  相似文献   
993.
It has been established through several decades of research that children's home environments significantly influence their development. Many researchers have also been interested in expanding research beyond indirect measures of the home environment, such as socioeconomic status, to help understand the nature of specific environmental mechanisms which influence early behavior and cognitive development. The Home Observation for Measurement of the Environment (HOME) Inventory was developed to meet these needs. Specifically, HOME measures the quality of stimulation in a child's early family environment. Almost all studies of the approach's reliability and validity have been conducted with US samples. HOME is, however, being used in other countries. The authors report their findings from a study of whether the psychometric properties of HOME based upon US samples parallel those found in Costa Rica, and whether HOME discriminates between Costa Rican environments with different associations to child health and development. Focus centers upon the infant/toddler version of the HOME Inventory. HOME data for 183 healthy Costa Rican infants were compared to the original HOME standardization sample from Little Rock, Arkansas. The study found the HOME Inventory to be helpful in identifying children at risk for delayed development in this Latin American sample. Lower HOME scores related to a shorter duration of breastfeeding and differentiated children with iron deficiency anemia in infancy, a condition associated with long-lasting developmental disadvantage.  相似文献   
994.
995.
On Bohm's formulation of quantum mechanics particles always have determinate positions and follow continuous trajectories. Bohm's theory, however, requires a postulate that says that particles are initially distributed in a special way: particles are randomly distributed so that the probability of their positions being represented by a point in any regionR in configuration space is equal to the square of the wave-function integrated overR. If the distribution postulate were false, then the theory would generally fail to make the right statistical predictions. Further, if it were false, then there would at least in principle be situations where a particle would approach an eigenstate of having one position but in fact always be somewhere very different. Indeed, we will see how this might happen even if the distribution postulate were true. This will help to show how loose the connection is between the wave-function and the positions of particles in Bohm's theory and what the precise role of the distribution postulate is. Finally, we will briefly consider two attempts to formulate a version of Bohm's theory without the distribution postulate.  相似文献   
996.
This study investigates gender similarity in the effects of birth order upon political leadership. Town supervisors were the leaders studied as there are a considerable number of women who attain this level of leadership. Questionnaires about birth order and family size were gained from 66 women who were town supervisors in New York State in 1992, and compared to a randomly selected sample of 57 male town supervisors. It was found that women as well as men town supervisors were more likely to have been first born in their families. However, whereas gender does not apparently influence the relevance of birth order for leadership, it clearly does exert an influence on the level of political leadership attained. Women town supervisors gained their positions in towns that were considerably smaller than the towns led by the male supervisors. Discussion concerned the nature of family experiences that contribute to leadership training, including those that may be different for girls and boys. Further research is needed to clarify barriers to female assertion of political leadership at more senior levels, because as this study shows, female leadership is being trained in families.  相似文献   
997.
Book reviews     
Science as Salvation: a Modern Myth and its Meaning, Mary Midgley, 1994. London, Routledge x +256pp., Hb 04 15062713, £35; Pb 04 15107733, £8.99

Philosophical Naturalism, David Papineau, 1993 Oxford, Basil Blackwell xii +219pp., Hb 0631189025, £40; Pb 0631189033, £14.99

F. H. Bradley, Writings on Logic and Metaphysics, James W. Allard & Guy Stock (Eds), 1994. Oxford, Clarendon Press xv+357pp, Hb 0–198–24445–2, £40.00; Pb 0–198–24438‐X, £14.95

Invariance and Heuristics: Essays in Honour of Heinz Post, Steven French & Harmke Kamminga (Eds), 1993 Boston Studies in the Philosophy of Science, Vol. 148 Kluwer Academic Publishers, Dordrecht

Beyond Reason: Essays on the Philosophy of Paul Feyerabend, GONZALO MUNÉVAR (Ed.), 1991. Dordrecht, Kluwer Academic Publishers xxi + 535pp., hb, ISBN 0–7923–1272–4, £104.20

World Changes: Thomas Kuhn and the Nature of Science, Paul Horwich (Ed.), 1993. Cambridge, MA, Bradford Books/MIT Press vi + 356pp., pb, ISBN 0262581388, £14.95

Realism Rescued: How Scientific Progress is Possible, Jerold L. Aronson, Rom Harré & Eileen Cornell Way, 1994 London, Duckworth vii +213pp., Hb 0715624768, £30.00

Scientific Nihilism: On the Loss and Recovery of Physical Explanation, Daniel Athearn, 1994. State University of New York Press, Albany ix + 387pp., Hb ISBN 0–7914–1807–3, £52

Theism, Atheism, and Big Bang Cosmology, William Lane Craig & Quentin Smith, 1993. Oxford, Clarendon Press x +342pp., Hb 0198263481, £35; Pb 019826383X, £13.95  相似文献   

998.
999.
Factor analysis of 18 Likert-type items dealing with gender stereotypes about family roles was conducted and yielded two measures: one focused on marital roles and one focussed on child rearing. Respondents were parents of children in the third and fourth grades of a large industrialized city in the Midwest. The sample included 364 families equally divided between middle and lower class with 23% African American and 77% European American. For both scales, more stereotyped scores were obtained by parents who were lower in social status, less educated, full-time homemakers, African Americans, and fathers. Parents' scores related to a separate measure of children's stereotypes and the marital-role attitudes related to actual roles reported by family members. Daughters whose parents obtained less stereotyped scores had a more internal locus of control, showed a trend toward more independent coping skills, and—in the middle class—obtained higher scores on achievement tests.This research was supported by Grant No. 91-1437-91 from the William T. Grant Foundation.  相似文献   
1000.
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