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911.
Previous research has yielded mixed results regarding the effects of age on innovation‐related behavior (IRB; i.e., generating, disseminating, and implementing new ideas). This paper hypothesizes that the relationship of age with IRB is jointly moderated by undermining behavior on the part of the supervisor and the extent to which the employee possesses a proactive personality. We collected data from 196 employees at three points in time over a one‐year period. Results supported the hypothesized 3‐way interaction of age, supervisor undermining, and proactive personality on IRB. As predicted, highly proactive older workers responded to high supervisor undermining with more IRB, whereas older workers low on proactive personality responded to high supervisor undermining with less IRB. On the other hand, when supervisor undermining was low, proactive personality did not moderate the relationship of age with IRB. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
912.
Although researchers have often found positive relationships between organizational citizenship behavior (OCB) and performance rating, very few studies have scrutinized the team contexts in which such relationships exist. This study examines how OCB influences job performance ratings within different team cultures, as measured by team collectivism and individualism. On the basis of multilevel data collected from 81 teams working at a multinational bank in Hong Kong, team collectivism and individualism were found to moderate the OCB–performance rating relationship such that OCB targeting individuals improved rated performance in highly collectivistic teams only, whereas only organizational OCB produced a significant improvement in highly individualistic teams. The implications of these findings and directions for future research directions are discussed here. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
913.
This paper examines the role of proactive personality in the receipt of informal mentoring received (i.e., psychosocial and career‐related mentoring) among a sample of 174 early career employees in China. The regression results indicated that networking behavior mediated the relationship between proactive personality and career‐related mentoring, whereas voice behavior mediated the relationship between proactive personality and psychosocial mentoring. Furthermore, core self‐evaluations moderated the aforementioned two indirect relationships such that they were stronger at higher levels of core self‐evaluations. Our analyses also showed that the moderating effects occurred at the first stage of the indirect relationships. We discuss the theoretical and practical implications of these findings. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
914.
交通事故致因中的人为因素分析   总被引:2,自引:0,他引:2  
为改善交通安全状况,减少交通事故,从最主要的因素——人为因素出发,分析其影响。导致事故发生的主要原因是:驾驶员处理交通事件的能力(包括新手、老年、酒精、药物、疲劳、压力等),驾驶员在驾驶时采取冒险行为(包括不正确使用安全带、超速、犯罪、自杀等)。结果表明:新手驾驶、饮酒驾驶、疲劳驾驶、不正确使用安全带驾驶等仍是影响交通安全的主要因素。  相似文献   
915.
A study was undertaken to investigate whether driver celeration (overall mean speed change) behavior can predict traffic accident involvement. Also, to test whether acceleration, deceleration or the combined celeration measure was the better predictor. Bus driver celeration behavior was measured repeatedly in real traffic, driving en route, and correlated with accidents for which the drivers were deemed at least partly responsible. Correlations around .20 were found in several samples between celeration behavior and culpable accidents for a 2-year period. The results show that although celeration behavior is only semi-stable over time, it predicts with some accuracy individual accident involvement over 2 years. The predictive power of acceleration and deceleration was slightly lower than the combined measure, in accordance with theory. The correlations found were strong enough to warrant the use of celeration behavior as a predictive variable for transportation companies in their safety work.  相似文献   
916.
PROBLEM: This paper evaluates the stopping propensity of drivers at matured in-service red light camera (RLC) signalized T-intersections after a number of years of camera operation. METHOD: A special-purpose data logger working in conjunction with loop sensors was used to gather traffic parameters, vehicle stopping/crossing movements, and signal phases at camera (treatment) and noncamera (comparison) approaches. Logistic modeling was employed to determine the stopping/crossing decisions of civilian vehicle drivers in response to the onset of yellow (amber) with traffic and the associated situational and behavioral variables, including their interactions. SUMMARY: The propensity to stop at camera approaches was about 17 times more than at noncamera approaches. This finding strongly affirmed the positive effect of RLC in encouraging drivers to stop. The likelihood to stop was about 6.5 times higher for an approach that faces an opposing right-turn conflict immediately after the onset of red. Higher stopping propensity was also more prevalent during weekdays and in periods of low traffic volumes. IMPACT ON INDUSTRY: The findings provided an objective measure on the effectiveness of RLC that would be useful to evaluate intersections for camera installation as well as on the implementation and operational aspects of RLC program.  相似文献   
917.
ABSTRACT The term “institution” and several variants are used frequently in the literature on metropolitan water management. The state-of-the art investigation on which this paper is based revealed that 1) many uses of the term do not include careful definitions; 2) many users of the term seemed unaware of the general, theoretical literature on the subject of institutions; 3) there was little consistency among uses, either in the practical literature dealing with water or in the conceptual literature dealing with theories of institutions or institutionalization; 4) some usages were without significant meaning; 5) in many cases the term was used as a kind of “black box” to account for behavioral, societal, or managerial factors; 6) the term was often used as a synonym for “organization”. This latter use is frequently found in federal reports, including National Water Commission studies, and is most unfortunate because it tends to slight significant social-psychological factors. A suggested definition is: “An institution is the structured result or outcome of a process by which values are articulated, arranged, and communicated, having continuity over time, and influencing behavior of persons who did not necessarily participate in formulating those values (norms).”  相似文献   
918.
Foraging behavior and the mechanisms that regulate foraging activity are important components of social organization. Here we test the hypothesis that brood pheromone modulates the sucrose response threshold of bees. Recently the honeybee proboscis extension response to sucrose has been identified as a ”window” into a bee’s perception of sugar. The sucrose response threshold measured in the first week of adult life, prior to foraging age, predicts forage choice. Bees with low response thresholds are more likely to be pollen foragers and bees with high response thresholds are more likely to forage for nectar. There is an associated genetic component to sucrose response thresholds and forage choice such that bees selected to hoard high quantities of pollen have low response thresholds and bees selected to hoard low quantities of pollen have higher response thresholds. The number of larvae in colonies affects the number of bees foraging for pollen. Hexane-extractable compounds from the surface of larvae (brood pheromone) significantly increase the number of pollen foragers. We tested the hypothesis that brood pheromone decreases the sucrose response threshold of bees, to suggest a pheromone- modulated sensory-physiological mechanism for regulating foraging division of labor. Brood pheromone significantly decreased response thresholds as measured in the proboscis extension response assay, a response associated with pollen foraging. A synthetic blend of honeybee brood pheromone stimulated and released pollen foraging in foraging bioassays. Synthetic brood pheromone had dose-dependent effects on the modulation of sucrose response thresholds. We discuss how brood pheromone may act as a releaser of pollen foraging in older bees and a primer pheromone on the development of response thresholds and foraging ontogeny of young bees. Received: 24 May 2000 / Revised: 26 September 2000 / Accepted: 15 October 2000  相似文献   
919.
920.
Field and laboratory studies compared two features of larval behavior in a pair of predacious sisterspecies of green lacewings: one (Chrysopa slossonae) a specialist on a single species of colonial aphids (the woolly alder aphid) that occur on branches and trunks of alder trees, the other (C. quadripunctata) a general aphid feeder whose primary prey is dispersed on foliage of diverse types of trees. First, a few hours after hatching, larvae of the two species develop significantly different phototactic responses; the differences correspond well with the spatial distributions of their prey. Most C. slossonae exhibited negative phototaxis, a response that helps move hatchlings inward on alder trees toward the woolly alder aphid colonies, whereas most C. quadripunctata hatchlings showed positive orientation to light, a response that tends to keep them in tree canopies with their prey. Second, in greenhouse experiments, a significantly greater proportion of C. slossonae larvae (second instars) molted within woolly alder aphid colonies and remained with the aphids than did C. quadripunctata larvae. These differences indicate that the specialist larvae have evolved a high degree of behavioral fidelity to their prey. However, larvae (second instars) of the two species that were released near ant-tended woolly alder aphid colonies in the field had similar recovery (= survival) rates. Consequently, natural selection may not act on behavioral traits that influence larval fidelity to prey during the late second and early third instars.  相似文献   
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