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121.
Military experience is an important turning point in a person's life and, consequently, is associated with important life outcomes. Using a large longitudinal sample of German males, we examined whether personality traits played a role during this period. Results indicated that personality traits prospectively predicted the decision to enter the military. People lower in agreeableness, neuroticism, and openness to experience during high school were more likely to enter the military after graduation. In addition, military training was associated with changes in personality. Compared with a control group, military recruits had lower levels of agreeableness after training. These levels persisted 5 years after training, even after participants entered college or the labor market. This study is one of the first to identify life experiences associated with changes in personality traits. Moreover, our results suggest that military experiences may have a long-lasting influence on individual-level characteristics.  相似文献   
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The pipeline toward careers in science, technology, engineering, and mathematics (STEM) begins to leak in high school, when some students choose not to take advanced mathematics and science courses. We conducted a field experiment testing whether a theory-based intervention that was designed to help parents convey the importance of mathematics and science courses to their high school-aged children would lead them to take more mathematics and science courses in high school. The three-part intervention consisted of two brochures mailed to parents and a Web site, all highlighting the usefulness of STEM courses. This relatively simple intervention led students whose parents were in the experimental group to take, on average, nearly one semester more of science and mathematics in the last 2 years of high school, compared with the control group. Parents are an untapped resource for increasing STEM motivation in adolescents, and the results demonstrate that motivational theory can be applied to this important pipeline problem.  相似文献   
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This study examined interventions for addition and subtraction that were implemented through single-case design (SCD) research studies. We attempted to extend prior SCD meta-analyses by examining differences in effect sizes across several moderating variables and by including a novel index of effect, improvement rate difference (IRD). We also examined the extent to which effect sizes differed by degree of experimental control achieved in the studies. Forty-seven effect sizes were obtained across 11 studies. IRD effect sizes ranged from .59 to .90 and suggested a moderate to large effect for the math interventions. Variables that appeared to moderate the effects were student age, time spent in intervention, and intervention type. We also identified a relationship between experimental control and the obtained effect sizes. Findings indicated that further SCD research in basic arithmetic and rigorous experiments are necessary to establish an evidence base that accurately characterizes intervention effectiveness.  相似文献   
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In a recent editorial, Raymond Spier expresses skepticism over claims that climate change is driven by human actions and that humanity should act to avoid climate change. This paper responds to this skepticism as part of a broader review of the science and ethics of climate change. While much remains uncertain about the climate, research indicates that observed temperature increases are human-driven. Although opinions vary regarding what should be done, prominent arguments against action are based on dubious factual and ethical positions. Thus, the skepticisms in the recent editorial are unwarranted. This does not diminish the general merits of skeptical intellectual inquiry.  相似文献   
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Communal predators may often need to make especially intricate foraging decisions, as a predator's success may depend on the actions of its neighbours. Here,we consider the decisions made by Portia africana, a jumping spider (Salticidae) that preys on other spiders, including Oecobius amboseli (Oecobiidae), a small prey spider that lives under small sheets of silk (nests) on the walls of buildings. P. africana juveniles settle near oecobiid nests and then ambush oecobiids as they leave or enter the nest. Two or more P. africana juveniles sometimes settle at the same nest and, when an oecobiid is captured, the P. africana juveniles may share the meal. We investigated the joining decisions made by na?ve P. africana juveniles. Experiments were based on using lures (dead spiders positioned in lifelike posture) arranged in a series of 17 different scenes defined by the presence/absence of a nest, the lure types present and the configuration of the lures and the nest. Our findings imply that P. africana juveniles make remarkably precise predatory decisions, with the variables that matter including whether a nest is present, the identity of spiders inside and outside a nest and how spiders are positioned relative to each other and the nest.  相似文献   
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ObjectivesThe purpose of this study was to examine the effects of different scoring protocols used with instruments designed to assess motivation in line with Organismic Integration Theory (OIT; Deci & Ryan, 2002).DesignThis study used non-probability based sampling within a cross-sectional (survey) design.MethodsParticipants across four samples (N's ranged from 236 to 1200) completed either (a) the Behavioral Regulation in Exercise Questionnaire (BREQ), (b) the BREQ-2, or (c) the BREQ-2R in conjunction with a self-report assessment of physical activity behavior.ResultsParticipants endorsed more self-determined than controlled motives for physical activity. Identified regulation was the dominant correlate of more frequent physical activity behavior. The link between external regulation and physical activity was consistently weak. Multiple regression analyses revealed identified regulation was the strongest predictor of physical activity compared with other motives. Regression models using omnibus scoring protocols accounted for less variance in physical activity behavior in contrast to an item-aggregation scoring protocol.ConclusionsIdentified regulation may be a key source of physical activity motivation in adults. The scoring protocol used with OIT-based instruments represents an important consideration for advancing physical activity research.  相似文献   
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Authenticity judgments involve how individuals distinguish what appears to be real versus fake, genuine versus phony. In this investigation, we bring authenticity into the laboratory to assess it in a manner quite different from most extant approaches. Taking a Peircian semiotic view in a context of environmentally conscious consumption, we develop and test a set of hypotheses concerning the effects of indexical and iconic cues to an authentic “green” product meaning. Results suggest that effects of these indicators of authenticity can be induced in a controlled manner with products being assessed as more or less “green” on the basis of particular cue arrangements. Furthermore, the effectiveness of these semiotic cues is moderated by a basic distinction among products. Taken together, the results provide evidence supporting a meaning validation process as the basis of authenticity judgments and suggest new directions for theory building in a domain where there is substantial practitioner interest. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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