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61.
There are two competing theoretical perspectives on how job tenure might affect job performance. Human capital theory suggests that as knowledge and skill increase with greater tenure, job performance will improve as well. In contrast, the literature on job design suggests that as job tenure increases, employees are likely to become more bored and less motivated at work. Consequently, the gains from human capital acquisition might be offset by losses of motivation. To examine these competing perspectives, we conducted meta-analyses on the relationships of job tenure with four types of job performance: core task performance, citizenship behavior, creativity and innovative behavior, and counterproductive work behavior. The results support the second perspective, as both the linear and curvilinear relationships of job tenure with the four types of job performance are weak. Further, the results do not change in strength across type of research design, job industry, age, or gender.  相似文献   
62.
Automated reasoning about uncertain knowledge has many applications. One difficulty when developing such systems is the lack of a completely satisfactory integration of logic and probability. We address this problem directly. Expressive languages like higher-order logic are ideally suited for representing and reasoning about structured knowledge. Uncertain knowledge can be modeled by using graded probabilities rather than binary truth values. The main technical problem studied in this paper is the following: Given a set of sentences, each having some probability of being true, what probability should be ascribed to other (query) sentences? A natural wish-list, among others, is that the probability distribution (i) is consistent with the knowledge base, (ii) allows for a consistent inference procedure and in particular (iii) reduces to deductive logic in the limit of probabilities being 0 and 1, (iv) allows (Bayesian) inductive reasoning and (v) learning in the limit and in particular (vi) allows confirmation of universally quantified hypotheses/sentences. We translate this wish-list into technical requirements for a prior probability and show that probabilities satisfying all our criteria exist. We also give explicit constructions and several general characterizations of probabilities that satisfy some or all of the criteria and various (counter)examples. We also derive necessary and sufficient conditions for extending beliefs about finitely many sentences to suitable probabilities over all sentences, and in particular least dogmatic or least biased ones. We conclude with a brief outlook on how the developed theory might be used and approximated in autonomous reasoning agents. Our theory is a step towards a globally consistent and empirically satisfactory unification of probability and logic.  相似文献   
63.
Older adults commonly experience declines in prospective memory, which describes one’s ability to “remember to remember,” and can adversely affect instrumental activities of daily living and healthcare compliance. However, the extent to which prospective memory failures may influence quality of life in typically aging older adults is not well understood. One-hundred and four community-dwelling older Australians (aged 50 to 82 years) were administered a comprehensive, neuropsychological battery that included the Memory for Intentions Screening Test (MIST), Prospective and Retrospective Memory Questionnaire (PRMQ), Instrumental Activities of Daily Living Questionnaire (IADLQ), and World Health Organization Quality of Life-8 (WHOQOL-8). Multiple regressions controlling for negative affect, medical comorbidities, and other neurocognitive functions revealed an interaction between prospective memory and instrumental activities of daily living in the concurrent prediction of quality of life. Among the 39 older adults who reported multiple problems on the IADLQ, lower performance-based prospective memory (MIST) and higher self-reported prospective memory failures in daily life (PRMQ) were significantly associated with lower quality of life (WHOQOL-8). Conversely, no significant associations were observed between prospective memory and quality of life in the 65 participants without IADL problems. Prospective memory difficulties adversely impact quality of life in community-dwelling older adults who experience problems independently managing their instrumental activities of daily living. These findings extend prior literature showing that prospective memory plays a unique role in the real-world outcomes of older adults and clinical populations and highlight the need to develop effective strategies to enhance prospective memory functioning in these vulnerable groups.  相似文献   
64.
This study of Asian American, Caucasian American, and Chinese college students examined the relationship between participants' career choices and parental influence. The results showed that the Asian American and Chinese college students were more likely than were Caucasian American students to choose Investigative occupation types (J. L. Holland, 1985) and that their choices were more likely to be influenced by their family. Este estudio de estudiantes universitarios Asiático Americanos, Caucásico Americanos, y Chinos examino la relación entre la elección de carrera de los participantes y la influencia de los padres. Los resultados mostraron que los estudiantes universitarios Asiático Americanos y Chinos fueron más probables a escojer los tipos de ocupación Investigativos (J. L. Holland, 1985) y a ser mas influenciados por su familia, que los estudiantes Caucásico Americanos.  相似文献   
65.
中学生学业成就归因与学习动力的相关研究   总被引:2,自引:0,他引:2  
用自编问卷对913名中学生学业成就归因和学习动力状况进行了调查,发现: (1)整体上看中学生较多使用内在原因和可控原因解释自己的学习成绩; (2)不同性别和不同年级学生有不同的归因倾向; (3)归因倾向与学习动力有明显联系,使用因子分析法得到“自挫因子”对学习动力有很大的消极影响。本文还就如何进行归因训练进行了讨论。  相似文献   
66.
以4-8岁儿童和大学生为被试,用虚拟生物图片为材料,采用2(不提供背景知识和提供背景知识)×6(年龄)的实验设计,考察背景知识对被试分类活动的影响及其年龄特点。结果发现:(1)两种实验条件下均有显著的年龄差异。(2)提供背景知识与否对不同年龄被试分类活动的影响不同,对4-5岁儿童分类活动的影响不显著,对6-8岁儿童及大学生分类活动的影响显著。  相似文献   
67.
This study of 230 predominantly poor Hispanic and African American women aged 25 to 61 years living with HIV/AIDS in New York City revealed high levels of both sexual (39%) and physical (44%) trauma before the age of 16. Both types of early trauma were correlated with later trauma, and all forms of trauma were significantly associated with current perceived health. In multivariate analyses controlling for relevant covariates, the Powerful Others and Internal Control subscales of the Multidimensional Health Locus of Control Scales (K. A. Wallston, B. S. Wallston, & R. DeVellis, 1978) acted as independent predictors of perceived health rather than (as hypothesized) mediators of the association between trauma and perceived health. Findings underscore the importance of addressing trauma and perceptions of control over one's physical health in the provision of health services to HIV-positive women.  相似文献   
68.
There is increasing evidence that inadequate family environments (family material environment and family psychosocial environment) are not only social problems but also factors contributing to adverse neurocognitive outcomes. In the present study, the authors investigated the relationship among family environments, children's naturalistic affective state, self-reported stress, and executive functions in a sample of 157 Chinese families. These findings revealed that in inadequate family material environments, reduced children's cognitive flexibility is associated with increased naturalistic negative affectivity and self-reported stress. In addition, naturalistic negative affectivity mediated the association between family expressiveness and children's cognitive flexibility. The authors used a structural equation model to examine the mediation model hypothesis, and the results confirmed the mediating roles of naturalistic negative affectivity and self-reported stress between family environments and the cognitive flexibility of Chinese children. These findings indicate the importance of reducing stress and negative emotional state for improving cognitive functions in children of low socioeconomic status.  相似文献   
69.
Rare or low probability targets are detected more slowly and/ or less accurately than higher probability counterparts. Various proposals have implicated perceptual and response-based processes in this deficit. Recent evidence, however, suggests that it is attentional in nature, with low probability targets requiring more attentional resources than high probability ones to detect. This difference in attentional requirements, in turn, suggests the possibility that low and high probability targets may have different susceptibilities to attention capture, which is also known to be resource-dependent. Supporting this hypothesis, we found that, once attentional resources have begun to be engaged by detection processes, low, but not high, probability targets have a reduced susceptibility to capture. Our findings speak to several issues. First, they indicate that the likelihood of attention capture occurring when a given task-relevant stimulus is being processed is dependent, to some extent, on how said stimulus is represented within mental task sets. Second, they provide added support for the idea that the behavioural deficit associated with low probability targets is attention-based. Finally, the current data point to reduced top-down biasing of target templates as a likely mechanism underlying the attentional locus of the deficit in question.  相似文献   
70.
Extracting general rules from specific examples is important, as we must face the same challenge displayed in various formats. Previous studies have found that bimodal presentation of grammar‐like rules (e.g. ABA) enhanced 5‐month‐olds’ capacity to acquire a rule that infants failed to learn when the rule was presented with visual presentation of the shapes alone (circle‐triangle‐circle) or auditory presentation of the syllables (la‐ba‐la) alone. However, the mechanisms and constraints for this bimodal learning facilitation are still unknown. In this study, we used audio‐visual relation congruency between bimodal stimulation to disentangle possible facilitation sources. We exposed 8‐ to 10‐month‐old infants to an AAB sequence consisting of visual faces with affective expressions and/or auditory voices conveying emotions. Our results showed that infants were able to distinguish the learned AAB rule from other novel rules under bimodal stimulation when the affects in audio and visual stimuli were congruently paired (Experiments 1A and 2A). Infants failed to acquire the same rule when audio‐visual stimuli were incongruently matched (Experiment 2B) and when only the visual (Experiment 1B) or the audio (Experiment 1C) stimuli were presented. Our results highlight that bimodal facilitation in infant rule learning is not only dependent on better statistical probability and redundant sensory information, but also the relational congruency of audio‐visual information. A video abstract of this article can be viewed at https://m.youtube.com/watch?v=KYTyjH1k9RQ  相似文献   
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