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11.
Five experiments examined the role of resource evaluability on giving. We systematically varied participants' resources they and another potential donor received and whether they could donate to a recipient either by themselves or with the other donor. Participants in the relative advantage condition received more resources than the other donor, and those in the relative disadvantage condition received fewer resources than the other donor. The presence of the other donor made participants' resources evaluable and shaped giving: Relatively disadvantaged participants were proportionally more generous than advantaged participants but only when they could evaluate their resources. Neither the mere presence of others nor reputational concerns could explain the results. Exploratory mediation and moderation analyses further showed that relatively disadvantaged participants give proportionally more the higher and the more equal they perceive their status to the advantaged donor. This shows that the generosity of those who have less does depend on how they evaluate their status compared to other donors. Our results provide insights into the question of why and when resource asymmetries between donors result in prosocial giving and can influence fundraising strategies of charitable organizations.  相似文献   
12.
People use editorial criteria to decide whether to say or to suppress potential arguments. These criteria constitute people's standards as to what effective and appropriate arguments are like, and reflect general interaction goals. A series of empirical investigations has indicated that the standards fall into three classes: those having to do with argument effectiveness, those concerned with personal issues for arguer and target, and those centered on discourse quality. The essay also sketches the affinities certain types of people have for the different criteria.  相似文献   
13.
人类颜色视觉的计算理论   总被引:2,自引:0,他引:2  
该文有机地结合了计算视觉理论和生态学视觉理论,指出颜色信息处理的根本任务是检测环境中的光不变量。在此基础上,作者提出了颜色视觉的计算理论以及计算理论本身的生物学标准。初级视觉计算是典型的不适定问题,动物的视觉系统则利用视环境中存在的条件将该不适定问题转化为定解问题。本文引入颜色视觉计算的免要条件,客观性约束,以及颜色认知的神经表象,证明了上述约束下颜色算法的存在性。本文给出了构造颜色知觉的基本假设。同时,该文还讨论了与上述问题密切相关的几个基本问题:神经表象的完备性,主观色觉的客观性,明度知觉和颜色知觉的统一,人类主观色觉的实现方式。  相似文献   
14.
Type A behaviour was measured in 250 boys and 245 girls (ages 3-7) using a Swedish version of Matthews' Youth Test for Health (MYTH). In addition, speech and voice characteristics (speed, loudness, response latency) were measured. Each child was independently rated by two play group leaders and measurements were repeated after a six month interval. Interrater reliability (first session) was 0.76 for both sexes and did not change with the age of the child. Boys obtained significantly (p less than 0.0001) higher scores than girls. Correlations over the six month period were 0.64 and 0.60 (p less than 0.001) for the two possible combinations of different raters and slightly higher (0.75 and 0.68, p less than 0.001) when the same rater was used. Two components of Type A behaviour were identified from a factor analysis of the data: impatience and competitiveness, and they accounted for 57% of the total variance. As for the total scale, boys obtained significantly higher scores than girls on both subscales. Scores on the competitiveness scale increased systematically with age. Speech and voice characteristics correlated significantly with Type A scores (total Type A behaviour: r = 0.50, using different raters, and 0.71, using the same raters, p less than 0.001) and, once again, boys obtained significantly (p less than 0.001) higher scores than girls. The results are in close agreement with the American findings from the original scale. It was concluded that the scale provides a reliable and valid instrument for measuring Type A or Type A-like behaviours in pre-school children.  相似文献   
15.
Eighty-four undergraduate students were randomly divided into left and right visual half-field groups. They were tested in either visual half-field with a percept-genetic test of anxiety and defense mechanisms (the MCT). The subjects also took a test of creative functioning (the CFT) and degree of lateralization in the MCT was related to level of creativity in the CFT. Subjects low in creativity were significantly lateralized on measures typical for the right visual half-field group (isolation and repression) and tended to differ on a left visual half-field measure (regressive strategies). For high creative subjects no differences were found between the visual half-field groups. Also, high creative persons more often responded with non-hemisphere-specific defenses than low creative ones. The results were interpreted as due to differing levels of transmission of information between the two hemispheres of the brain.  相似文献   
16.
The Jenkins Activity Survey (JAS) was administered to a normal population of randomly selected Danish adults, to patients consulting a cardiologist, and to physicians in order to compare those groups in terms of their coronary-prone (Type A) behaviour patterns. The standard procedure of rating the JAS was used in order to obtain scores for each of the four subscales: Type A (time urgency and ambitiousness), Factor S (speed and impatience) Factor H (hard-driving and competitive) and Factor J (job involvement). Gender differences were observed in the normal population for each of the four subscale scores, and age-related differences were obtained for Factor J. Elevated scores for Factor S were obtained by physicians and by people in the population who had a cardiovascular disorder. Physicians had also elevated scores for Factor J, whereas their Factor H scores tended to be reduced. No reliable differences in JAS subscale scores were observed between four groups of heart patients (i.e. angina pectoris, arterial hypertension, atrial fibrillation and atherosclerosis), although there was a tendency for Factor J to be elevated in atherosclerosis. The findings provide normal values for JAS scores in Danish men and women, and suggest that some facets of coronary-prone behaviour may be enhanced in Danish high-risk groups.  相似文献   
17.
Thirty-one families with pre-school children were examined with regard to Type A behaviour and cardiovascular and neuroendocrine measurements. Type A scores (MYTH) of the children from the ages of three to six were positively correlated with independent Type A measurements (Jenkins Activity Survey, Bortner Type A scale) of the parents (significant for fathers but not for mothers). The children's resting systolic blood pressures were significantly correlated with maternal and paternal values, while no significant familial aggregation was found for diastolic blood pressure, heart rate, catecholamine or cortisol excretion. The children's systolic and diastolic blood pressures and adrenaline excretion were significantly correlated between ages three and six. The results are consistent with the assumption that genetic as well as environmental factors contribute to the development of Type A behaviour. No significant association was found between Type A scores and physiological measurements during routine activities in the children or the adults.  相似文献   
18.
The present study describes the diagnostic profile of over 800 adolescents admitted to residential therapeutic community programs for treatment of drug abuse and related problems. The relationship between race/ethnicity and psychiatric disturbance is examined, and the association among these factors to outcome is investigated. Over 90% of the sample had a DSM-III-R nonsubstance diagnosis. There were significant differences among the race/ethnic groups on attention deficit-hyperactivity and the disruptive behavior and affective disorders. In general, African-American adolescents yielded the lowest rates of disturbance across all categories of disorders. There was no relationship among race/ethnicity, psychiatric disturbance, and 1-year posttreatment outcomes.  相似文献   
19.
We investigated the possibility that human-like fixed-interval performances would appear in rats given a variable-ratio history (Wanchisen, Tatham, & Mooney, 1989). Nine rats were trained under single or compound variable-ratio schedules and then under a fixed-interval 30-s schedule. The histories produced high fixed-interval rates that declined slowly over 90 sessions; differences as a function of the particular history were absent. Nine control animals given only fixed-interval training responded at lower levels initially, but rates increased with training. Despite differences in absolute rates, rates within the intervals and postreinforcement pauses indicated equivalent development of the accelerated response patterns suggestive of sensitivity to fixed-interval contingencies. The finding that the histories elevated rates without retarding development of differentiated patterns suggests that the effective response unit was a burst of several lever presses and that the fixed-interval contingencies acted on these units in the same way as for single responses. Regardless of history, the rats did not manifest the persistent, undifferentiated responding reported for humans under comparable schedules. We concluded that the shortcomings of animal models of human fixed-interval performances cannot be easily remedied by including a variable-ratio conditioning history within the model.  相似文献   
20.
This study examined stability and change in patterns of mother-infant interaction between 5 and 10 months and their relation to attachment security at 18 months. Cluster analysis was used to identify patterns of dyadic interaction. There was significant, but not substantial, stability in cluster membership from 5 to 10 months. For females, being in the most optimal cluster at 5 months related to subsequent attachment security, regardless of the 10-month pattern of interaction. For males, who were significantly more likely to be insecure than females, insecure attachment was predicted by negative change from 5 to 10 months (moving from a more optimal to a less optimal cluster).  相似文献   
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