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921.
Predictions from smoking-specific versus contextual models of smoking onset were tested with data from a 4-wave sample with 1,364 adolescents. Predictor variables were derived from stress-coping theory, social influence theory, and problem-behavior theory. In addition to groups of abstainers and experimenters, cluster analysis of smoking data indicated 3 groups who showed onset either in 7th grade (early onset), 9th grade (intermediate onset), or 10th grade (late onset). Almost all study variables discriminated the smoking groups from the abstainers. The onset groups were discriminated by Group X Time interactions showing differential changes in predictors (increases in risk factors and declines in protective factors), which occurred just prior to onset. The results generally support a contextual model of the onset process.  相似文献   
922.
World Health Organization age-, sex-, and cause-specific mortality data for the United States and 19 other democratic higher-income countries were utilized to assess the reliability and sensitivity of suicide certification for purposes of cross-national research. Data are found to be highly reliable across age and sex (rs > 0.92; P < 0.001). Relative discrepancies between official suicide rates (putative lower limits) and projected upper limits vary widely internationally. Austrian and Dutch suicide certification is the most sensitive. Least sensitive is certification for certain subpopulations in Finland, Greece, Ireland, Israel, and the United Kingdom. We recommend similar analyses be performed for routine, low-cost surveillance of suicide data quality, and to guide choice of population groups for multivariate comparative research.  相似文献   
923.
924.
Thomas M. King 《Zygon》2007,42(3):779-792
Several recent Roman Catholics who were known for their devotion have left accounts of their troubled faith. I consider three of these: St. Therese of Lisieux, Mother Teresa of Calcutta, and Pierre Teilhard de Chardin. Then I tell of the troubled atheism of Jean‐Paul Sartre. Finally, I use texts of Sartre and Teilhard to understand the unsettled nature of belief.  相似文献   
925.
In work done at the German Criminological Research Institute of Lower Saxony (KFN) various methods have been used to investigate how specific inappropriate media usage patterns affect academic performance in children and adolescents. The findings are paralleled by current international research indicating a negative relationship between these two variables. Based on a cross‐sectional survey of 5,529 fourth grade students and a longitudinal panel study with 1,157 primary schoolchildren, a key finding can be demonstrated: the more time students spend on consuming media and the more violent its contents are, the worse are their marks at school, even when controlling for vital factors such as family, educational, or immigrant background. In particular, boys who gender‐specifically are better equipped with electronic media devices, who partially have extensive media usage times and who strongly prefer violent media content, are at the risk of showing poor school performance. In fact, a decrease in academic performance of boys can be observed in German school statistics. By presenting first results of a school‐based intervention programme, a promising approach to the reduction of detrimental effects of electronic media use on school performance is introduced.  相似文献   
926.
The Myers-Briggs Type Indicator was administered to a sample of 61 monozygotic twins reared apart (MZA), 49 dizygotic twins reared apart (DZA), and 92 spouses, who participated in the Minnesota Study of Twins Reared Apart (MISTRA) from 1979 to 1995. Twins' scores on the continuous scales were subjected to behavior genetic model-fitting procedures. Extraversion-Introversion and Thinking-Feeling yielded heritabilities of about .60, consisting largely of nonadditive genetic variance. Sensing-Intuition and Judgment-Perception yielded heritabilities of about .40, consisting largely of additive genetic variance. Spouse correlations for three of the four scales were near zero and not statistically significant; one spouse correlation (Sensing-Intuition) was modestly positive and statistically significant.  相似文献   
927.
An approach to modeling cognitive development with a generative connectionist algorithm is described and illustrated with a new model of conservation acquisition. Among the conservation phenomena captured with this model are acquisition, the problem size effect, the length bias effect, and the screening effect. The simulations suggest novel explanations for sudden jumps in conservation performance (based on new representations of conservation transformations) and for the problem size effect (based on an analog representation of number). The simulations support the correlation-learning explanation of length bias (that length correlates with number during number altering transformations). Some conservation phenomena that so far elude computational modeling attempts are also discussed along with their prospects for capture. Suggestions are made for theorizing about cognitive development as well as about conservation acquisition. A variety of classic puzzles about cognitive development are addressed in the light of this model and similar models of other aspects of cognitive development.  相似文献   
928.
929.
Behavioral researchers have employed hypermedia-based software applications in their experiments for some time. More recently, interest in the World-Wide Web has developed among researchers in the social sciences, and popular use of this new medium continues to grow at an incredible rate. This paper describes Listener, a tool developed to log users’ hypermedia and World-Wide Web navigation behavior using Apple Macintosh computers in a laboratory setting. Listener is able to capture navigation actions through cached documents, overcoming some of the problems associated with analyzing standard web server logs.  相似文献   
930.
The Psychological Record - Previous studies have shown that conditional discrimination training procedures involving identity matching to complex samples can produce emergent arbitrary relations....  相似文献   
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