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951.
已有研究发现物体识别存在视角依赖效应,那么在真实物体搜索中是否也存在视角依赖效应呢?本研究采用物体阵列搜索任务,通过眼动技术探讨真实物体搜索中的视角依赖效应及其来源。结果发现:(1)图片提示的搜索绩效优于名称提示;(2)以名称提示时,常规视角的搜索绩效高于新异视角,与新异视角相比,以常规视角呈现的目标物体在扫描和确认阶段的注视点数较少且持续时间较短,表现出视角依赖效应;(3)以图片为提示时,搜索绩效与视角无关。由此可见,在以名称提示的物体搜索中,常规视角比新异视角条件下的注意引导更高效,对目标物体的确认也更快,扫描和确认阶段均存在视角依赖效应,支持目标模板的双功能理论。 相似文献
952.
基于进化领域的生命史理论,采用两种实验启动的途径探讨性别比、童年经济状况和女性长短期择偶偏好间的关系。结果表明:女性在长期择偶中更为重视男性的“好爸爸”和“好资源”,在短期择偶中更为重视男性的“好基因”;性别比在女性长期择偶的“好爸爸”偏好上具有显著主效应,在“女多男少”情境下女性对“好爸爸”的偏好水平会较“男多女少”时明显提高;性别比和童年经济状况在女性长期择偶“好爸爸”偏好上的交互效应显著:童年贫穷女性在“女多”情境下会明显提高对长期择偶“好爸爸”的偏好水平,童年富裕女性在性别失衡情境下对长期“好爸爸”的偏好保持相对稳定。 相似文献
953.
对315名粤港澳大湾区大学生进行问卷调查,分析他们前创业行动的情况并采用logistic回归研究其影响因素。结果发现,大学生前创业行动的参与度较为积极,但仍有进一步提升空间。而且,大学生的前创业行动受到了创业效能感、创业意愿和个体背景等内部因素的影响; 以及受到了创业政策熟悉度、大学生家庭所在地创业环境等外部变量的影响。研究结果对高校针对性开展创业教育具有一定的指导意义。 相似文献
954.
955.
Measuring Associations of the Department of Veterans Affairs' Suicide Prevention Campaign on the Use of Crisis Support Services 下载免费PDF全文
Elizabeth Karras PhD Naiji Lu PhD Guoxin Zuo PhD Xin M. Tu PhD Brady Stephens MS John Draper PhD Caitlin Thompson PhD Robert M. Bossarte PhD 《Suicide & life-threatening behavior》2016,46(4):447-456
Campaigns have become popular in public health approaches to suicide prevention; however, limited empirical investigation of their impact on behavior has been conducted. To address this gap, utilization patterns of crisis support services associated with the Department of Veterans Affairs' Veterans Crisis Line (VCL) suicide prevention campaign were examined. Daily call data for the National Suicide Prevention Lifeline, VCL, and 1‐800‐SUICIDE were modeled using a novel semi‐varying coefficient method. Analyses reveal significant increases in call volume to both targeted and broad resources during the campaign. Findings underscore the need for further research to refine measurement of the effects of these suicide prevention efforts. 相似文献
956.
A growing body of literature has shown that being victimized online is associated with poor mental health. Little is known about the factors that protect youth from the negative outcomes that may result from these victimization experiences, particularly those related to race. Using a risk and resilience framework, this study examined the protective function of ethnic identity and self-esteem among African Americans who experience online racial discrimination. For the sample of 125 adolescents, hierarchical regression results revealed that higher levels of ethnic identity and self-esteem significantly moderated the negative impact of online racial discrimination on anxiety levels. These findings show that ethnic identity and self-esteem can buffer the negative mental health outcomes associated with online racial discrimination, at least with respect to adolescents' anxiety. Findings from the current study have significant implications for adolescent adjustment given the increased time youth spend doing online activities. 相似文献
957.
Based on propositions derived from terror management theory (TMT), the current study proposes that people who are reminded of their mortality exhibit a higher degree of self-justification behavior to maintain their self-esteem. For this reason, they could be expected to stick with their previous decisions and invest an increasing amount of resources in those decisions, despite the fact that negative feedback has clearly indicated that they might be on a course toward failure (i.e., "escalation of commitment"). Our experiment showed that people who were reminded of their mortality were more likely to escalate their level of commitment by maintaining their current course of action. Two imaginary scenarios were tested. One of the scenarios involved deciding whether to send additional troops into the battlefield when previous attempts had failed; the other involved deciding whether to continue developing an anti-radar fighter plane when the enemy had already developed a device to detect it. The results supported our hypothesis that mortality salience increases the tendency to escalate one's level of commitment. 相似文献
958.
Inductive generalization of novel properties to same-category or similar-looking objects was studied in Chinese preschool children. The effects of category labels on generalizations were investigated by comparing basic-level labels, superordinate-level labels, and a control phrase applied to three kinds of stimulus materials: colored photographs (Experiment 1), realistic line drawings (Experiment 2), and cartoon-like line drawings (Experiment 3). No significant labeling effects were found for photos and realistic drawings, but there were significant effects for cartoon-like drawings. Children made mostly (>70%) category-based inferences about photographs whether or not labels were provided (Experiment 1). Children showed a bias toward category-based inferences about realistic drawings (Experiment 2) but did so only when labels were provided. Finally, children made mostly appearance-based generalizations for cartoon-like drawings (Experiment 3). However, labels (basic or superordinate level) reduced appearance-based responses. Labeling effects did not depend on having identical labels; however, identical superordinate labels were more effective than different basic-level labels for the least informative stimuli (i.e., cartoons). Thus, labels sometimes confirm the identity of ambiguous items. This evidence of labeling effects in Mandarin-speaking Chinese children extends previous findings beyond English-speaking children and shows that the effects are not narrowly culture and language specific. 相似文献
959.
960.
We defend a set of acceptance rules that avoids the lottery paradox, that is closed under classical entailment, and that accepts uncertain propositions without ad hoc restrictions. We show that the rules we recommend provide a semantics that validates exactly Adams?? conditional logic and are exactly the rules that preserve a natural, logical structure over probabilistic credal states that we call probalogic. To motivate probalogic, we first expand classical logic to geo-logic, which fills the entire unit cube, and then we project the upper surfaces of the geo-logical cube onto the plane of probabilistic credal states by means of standard, linear perspective, which may be interpreted as an extension of the classical principle of indifference. Finally, we apply the geometrical/logical methods developed in the paper to prove a series of trivialization theorems against question-invariance as a constraint on acceptance rules and against rational monotonicity as an axiom of conditional logic in situations of uncertainty. 相似文献