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971.
Human participants and recurrent (“connectionist”) neural networks were both trained on a categorization system abstractly similar to natural language systems involving irregular (“strong”) classes and a default class. Both the humans and the networks exhibited staged learning and a generalization pattern reminiscent of the Elsewhere Condition (Kiparsky, 1973). Previous connectionist accounts of related phenomena have often been vague about the nature of the networks’ encoding systems. We analyzed our network using dynamical systems theory, revealing topological and geometric properties that can be directly compared with the mechanisms of non‐connectionist, rule‐based accounts. The results reveal that the networks “contain” structures related to mechanisms posited by rule‐based models, partly vindicating the insights of these models. On the other hand, they support the one mechanism (OM), as opposed to the more than one mechanism (MOM), view of symbolic abstraction by showing how the appearance of MOM behavior can arise emergently from one underlying set of principles. The key new contribution of this study is to show that dynamical systems theory can allow us to explicitly characterize the relationship between the two perspectives in implemented models.  相似文献   
972.
采用客体回溯范式,以客体预览利化效应(object specific previewing benefit, OSPB)作为指标,考察表面特征线索对客体保持的作用。实验1使用双向隧道创建时空线索不明确的条件,研究表面颜色特征线索的作用。实验2使用单向隧道使时空线索明确,研究表面颜色特征线索与时空线索一致、冲突情境下的客体保持。实验1和实验2均出现了OSPB效应,且实验2冲突情境的OSPB效应低于一致情境。研究结果表明在时空线索不明确的条件下,仅凭表面颜色特征线索就能实现客体保持;在时空线索明确的条件下,时空线索是客体保持的主要线索,同时表面颜色特征线索也起一定的作用。  相似文献   
973.
为探究多元社会认同如何通过群体情绪、自我和群体效能路径,影响现实或网络集体行动参与,研究者分别以中日撞船事件、利比亚事件和就业性别歧视现象为背景蓝本,开展问卷调查和实验研究,结果发现:群体愤怒情绪主要对现实集体行动有显著影响,效能感对现实和网络集体行动皆有显著影响;与事件相关的、更大范畴的社会类别认同,通过情绪路径或效能路径影响集体行动参与,与集体行动组织方的认同则只通过效能路径影响集体行动参与;两类社会认同与两条路径之间是调节而非中介关系。不同事件背景与不同行动场域下的综合分析表明网络集体行动参与决策更具工具理性特征。  相似文献   
974.
Bioethics and health researchers often turn to Islamic jurisconsults (fuqahā’) and their verdicts (fatāwā) to understand how Islam and health intersect. Yet when using fatwā to promote health behavior change, researchers have often found less than ideal results. In this article we examine several health behavior change interventions that partnered with Muslim religious leaders aiming at promoting organ donation. As these efforts have generally met with limited success, we reanalyze these efforts through the lens of the theory of planned behavior, and in light of two distinct scholarly imperatives of Muslim religious leaders, the ?ilmī and the islāhī. We argue for a new approach to health behavior change interventions within the Muslim community that are grounded in theoretical frameworks from the science of behavior change, as well the religious leadership paradigms innate to the Islamic tradition. We conclude by exploring the implications of our proposed model for applied Islamic bioethics and health research.  相似文献   
975.
The dominant research paradigm in sales research involves testing theory through empirical research. Nascent or underdeveloped research areas, however, may lack or have inadequate existing theories to explain sales-related phenomena. In these cases, sales researchers require a theory-generating methodological approach. Qualitative research designs are useful in this pursuit. The purpose of this article is to provide an exposition of one such qualitative research design – grounded theory. To this end, the foundational processes of grounded theory methodology are discussed. The results of a review of grounded theory examinations conducted in sales research are also provided, and current practices utilized by sales grounded theorists are discussed. Based on this review, future directions in substantive areas and methodological practices are provided. This article aims to serve as a resource for sales scholars wishing to know what grounded theory examinations have been conducted, how to implement grounded theory research and what avenues are available for future grounded theory sales research.  相似文献   
976.
Abstract

A survey of 619 Detroit-area women was conducted in order to understand why women do or do not perform breast self-examination and obtain or not obtain professional breast examinations. The survey assessed these behaviors and women's beliefs about (a) their susceptibility to breast cancer, (b) the seventy or seriousness of breast cancer, (c) the benefits of breast examinations and (d) the costs or disadvantages of the examinations. Separate sets of questions measured seventy of breast cancer when it is treated (a) late (seventy-late) and (b) promptly (seventy-early). Predictions were derived by combining the health belief model with the theory of subjective expected utility. Path analysis supported most predictions of the combined theory. As predicted, high severity-late increased perceived benefit, high seventy-early decreased benefit, and perceived benefit mediated the effects of seventy on behavior. Implications for understanding health decisions, measuring health beliefs, and modifying health behaviors are discussed.  相似文献   
977.
Local comparisons with a few people displace the influence of general comparisons with many people during self-evaluation of performance and ability. The current research examined whether this local dominance effect obtains in the domain of health risk perception, an outcome of critical importance given its direct relation to preventative health behaviours. Participants received manipulated feedback indicating that their risk of diabetes (Study 1) or a serious car accident (Study 2) ranked above average or below average relative to numerous peers. Additionally, some participants were told that their risk ranked highest or lowest relative to a few peers. Participants evaluated their risk as significantly higher when they only knew that it ranked above average than below average. However, this effect was eliminated among participants who received additional local comparison information. These findings highlight the potential biasing influence of local comparison on everyday health judgment and behaviour.  相似文献   
978.
Moral norms and anticipated regret are widely used extensions to the theory of planned behaviour, yet there is some evidence to suggest that these constructs may conceptually overlap as predictors of intention. Two health-related behaviours with distinct moral implications (Study 1: organ donation registration, N?=?352 and Study 2: condom usage, N?=?1815) were therefore examined to ascertain whether moral norms and anticipated regret are indeed conceptually distinct. While evidence consistent with conceptual overlap was identified in Study 1, the evidence for such overlap in Study 2 was more ambiguous. In Study 3, a meta-analysis of existing literature revealed that the relationship between moral norms and anticipated regret was moderated by the extent of the moral implications arising from the behaviour under examination. Taken together, these findings suggest that conceptual overlap between moral norms and anticipated regret is more likely to occur among behaviours with obvious moral implications. Researchers wishing to examine the predictive utility of moral norms and anticipated regret among such behaviours would therefore be advised to aggregate these measures to form a composite variable (personal norms).  相似文献   
979.
The magnitude and predictors of longitudinal behavioral change are reported in a cohort of homosexual men at risk for AIDS. Self-reports of sexual behavior were obtained at two points in time separated by an interval of approximately six months. These self-reports were used to construct both dichotomous and continuous measures of changes in behavior consistent with reduction in the transmission of the AIDS virus (HIV). Although there was considerable variability in behavior. mean changes were consistently in the desired direction. Avoidance of anonymous sexual partners, monogamy, and modification of receptive anal sex to reduce exposure to semen by condom use or withdrawal prior to ejaculation appeared to be especially important in this cohort. Both multiple linear regression and multiple logistic regression were used to examine the relationship between a model of health behavior and these outcomes. Variables examined included knowledge of AIDS. perceived risk of AIDS. the perceived efficacy of behavior in reducing AIDS risk, difficulties with sexual impulse control, belief in biomedical technology to provide a prevention or cure, social norms supportive of behavioral change, and gay network affiliation. Of all these factors, only the availability of supportive peer norms was consistently, significantly and positively related to multiple measures of outcome. Differences between these analyses and longitudinal analyses reported elsewhere are discussed. These results suggest the policies regarding HIV antibody testing should be developed cautiously. taking account of the failure of a sense of risk to predict subsequent behavioral change. They also emphasize the important role of gay organizations in developing social norms supportive of behavioral risk reduction.  相似文献   
980.
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