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141.
Effects of timing of social isolation on play fighting and serious fighting were studied at different ages in male golden hamsters. Litters were isolated at 21, 35, and 65 days of age, and tested in a resident-intruder paradigm. Behaviors were compared within grous and with a fourth group of socially reared conspecifics. The earlier the pups were isolated, the more they engaged in play activities. Later, in adulthood, the aggression level of the same animals was retested using the same paradigm. The three isolated groups showed a high level of aggression, with significant differences among them. When compared with socially reared subjects, a reliable difference in the level of aggression was also found. These results support the view that early social experience is important, suggesting that isolation during early critical periods of socialization has a significant impact on play fighting, whereas short periods of isolation may be enough to trigger adult agonistic behavior. © 1994 Wiley-Liss, Inc.  相似文献   
142.
There is a frequent need to measure the degree of agreement among R observers who independently classify n subjects within K nominal or ordinal categories. The most popular methods are usually kappa-type measurements. When = 2, Cohen's kappa coefficient (weighted or not) is well known. When defined in the ordinal case while assuming quadratic weights, Cohen's kappa has the advantage of coinciding with the intraclass and concordance correlation coefficients. When > 2, there are more discrepancies because the definition of the kappa coefficient depends on how the phrase ‘an agreement has occurred’ is interpreted. In this paper, Hubert's interpretation, that ‘an agreement occurs if and only if all raters agree on the categorization of an object’, is used, which leads to Hubert's (nominal) and Schuster and Smith's (ordinal) kappa coefficients. Formulae for the large-sample variances for the estimators of all these coefficients are given, allowing the latter to illustrate the different ways of carrying out inference and, with the use of simulation, to select the optimal procedure. In addition, it is shown that Schuster and Smith's kappa coefficient coincides with the intraclass and concordance correlation coefficients if the first coefficient is also defined assuming quadratic weights.  相似文献   
143.
144.
A recent re-operationalisation of grandiose narcissism has resulted in the distinction of two narcissistic strategies based on the cognitive, affective-motivational and behavioural dynamics: admiration (assertive self-enhancement) and rivalry (antagonistic self-protection). The Narcissistic Admiration and Rivalry Questionnaire (NARQ) was developed to assess this model with two higher-order dimensions. However, cross-validations of the NARQ have not been extensively conducted across diverse population groups and languages. This study aimed to test the internal and external validity (through the relation with envy and self-esteem), reliability and cross-cultural equivalence of the Spanish version of the NARQ. The psychometric properties were evaluated in a Spanish sample (N = 310), and cross-cultural equivalence was tested in participants from Chile (N = 234) and Colombia (N = 256). The results supported the reliability and validity of the Spanish NARQ, as well as the cross-cultural equivalence across Spanish-speaking countries. In addition, we discuss obtained differences across Spanish, Chilean and Colombian sample within two narcissistic strategies.  相似文献   
145.
Pan  Junhao  Ip  Edward Haksing  Dubé  Laurette 《Psychometrika》2020,85(1):75-100
Psychometrika - Ansari et al. (Psychometrika 67:49–77, 2002) applied a multilevel heterogeneous model for confirmatory factor analysis to repeated measurements on individuals. While the mean...  相似文献   
146.
This study applies an intervention based on autonomy support through dialogic learning to examine effects on motivation and the promotion of physical activity and sport involvement during schoolchildren’s leisure time. One hundred and two primary school students, aged 11–13 years, participated (M = 10.93, SD = 0.75). The sample was divided into two groups: an experimental group (49 students) and a control group (53 students). A quasi-experimental study was conducted in physical education classes over the course of 9 months. Assessments of autonomy support from teachers, family, and peers; basic psychological needs; self-determined motivation in physical education and during leisure time; planned behavior variables; physical activity intention; and estimated and actual physical exercise behavior time were included in the model. Following the intervention, the results revealed that greater autonomy support by the teacher, the family and peers, satisfaction of the basic psychological needs, self-determined motivation during physical education class and during free time, greater perceived control, favorable attitude and intention to engage in physical activity contributed to the explanation of student physical activity involvement. These results suggest that when students receive extensive social support from diverse social agents that essential precursors to physical activity are strengthened and contribute to increased motivation and actual physical activity involvement. Efforts to promote effective communications with students and other pedagogical efforts, such as providing dialogic learning opportunities, should be considered in order to strengthen physical activity motivation and involvement in students.  相似文献   
147.
Immigrant naturalization is a rite of passage, making assimilationist attitudes particularly pronounced among host nationals. Three experimental studies investigate whether heritage culture maintenance violates expectations that citizenship should be deserved by proving strong attachment to the host nation (i.e., neoliberal communitarianism). Study 1 (N = 293) demonstrates that naturalization applicants’ high degree of heritage culture maintenance impairs application evaluations. Perceived attachment to the host nation and citizenship deservingness mediated this effect. Study 2 (N = 220) replicates results across two national contexts and reveals that heritage culture maintenance impairs evaluations only among naturalization applicants from devalued countries. Study 3 (N = 117) manipulates attachment to the host nation and shows that perceived citizenship deservingness mediates the negative effects of naturalization applicants' low attachment to the host nation on application evaluations. Overall, assimilationist attitudes among host nationals are best explained by the combination of neoliberal and communitarian criteria of evaluation.  相似文献   
148.
Laraudogoitia  Jon Pérez 《Philosophia》2020,48(3):1093-1099
Philosophia - Salmon (1970) was the first to speak explicitly of paradoxes of kinematics. In this short note I introduce a new class of infinity puzzles. Following natural terminology, they should...  相似文献   
149.
Sex Roles - The gender-neutral third-person pronoun singular hen was recently introduced in Swedish as a complement to she (hon) and he (han). The initiative to add hen initially received strong...  相似文献   
150.
Krahé  Barbara  Papakonstantinou  Lida 《Sex roles》2020,82(1-2):94-101
Sex Roles - Women’s average voice pitch has decreased in recent years, reducing the gap between men on this vocal dimension. The present study examined whether a woman speaking at a lower...  相似文献   
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