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151.
上世纪50年代,UFO目击者和加入这个事件的渲染者使事件急剧升温。1950年,弗朗克·斯库利(Frank Scully)发表了一本引起轰动的书,叫《追踪飞碟》。书中声称,一个飞碟坠毁在新墨西哥的阿兹特克东部的偏僻的高原沙漠上,飞碟的直径为99英尺,里面有16个外星人的尸体。斯库利自己并没有看见这个场景,仅仅是听别人说的。2年以后,发现这个故事是个骗局。关于飞碟坠毁的另一个故事也是发生在新墨西哥,地点是位于罗斯威尔西北部的75英里一处空军基地。据猜测,这次坠毁发生在1947年的7月,由此引发了一系列的事件和争论,并延续至今。坠毁是不容争论的,…  相似文献   
152.
The convergent and discriminant validity of subjective fit perceptions   总被引:2,自引:0,他引:2  
This study examined whether employees develop perceptions about 3 different types of fit: person-organization fit, needs-supplies fit, and demands-abilities fit. Confirmatory factor analyses of data from 2 different samples strongly suggested that employees differentiate between these 3 types of fit. Furthermore, results from a longitudinal design of 187 managers supported both the convergent and discriminant validity of the different types of fit perceptions. Specifically, person-organization fit perceptions were related to organization-focused outcomes (e.g., organizational identification, citizenship behaviors, turnover decisions), whereas needs-supplies fit perceptions were related to job- and career-focused outcomes (e.g., job satisfaction, career satisfaction, occupational commitment). Although demands-abilities fit perceptions emerged as a distinct construct, they were not related to hypothesized outcomes (e.g., job performance, raises).  相似文献   
153.
Eyewitness researchers have shown that witnesses accurately choosing the culprit out of a lineup reach their decisions more quickly than those erroneously choosing an innocent individual. However, this research is silent regarding how quickly or slowly witnesses must be, in absolute terms, to indicate that they are accurate or inaccurate. Across 4 studies, the authors discovered that a time boundary of roughly 10 to 12 s best differentiated accurate from inaccurate positive identifications. Witnesses making their identification faster than 10 to 12 s were nearly 90% accurate; those taking longer were roughly 50% accurate. This finding is consistent with previous research showing that accurate witnesses are more likely than inaccurate witnesses to reach their decisions automatically, that is, quickly, without conscious thought or effort.  相似文献   
154.
Killeen and Hall (2001) showed that a common factor called strength underlies the key dependent variables of response probability, latency, and rate, and that overall response rate is a good predictor of strength. In a search for the mechanisms that underlie those correlations, this article shows that (a) the probability of responding on a trial is a two-state Markov process; (b) latency and rate of responding can be described in terms of the probability and period of stochastic machines called clocked Bernoulli modules, and (c) one such machine, the refractory Poisson process, provides a functional relation between the probability of observing a response during any epoch and the rate of responding. This relation is one of proportionality at low rates and curvilinearity at higher rates.  相似文献   
155.
31 college age men and women who consume less than three caffeinated beverages per week agreed to participate as subjects in research on the effects of acute caffeine intake on low intensity task performance. All subjects performed two randomly administered test conditions: (1) caffeine (5 mg/kg) and (2) placebo on separate visits following an initial 1-hr. orientation visit. Subjects were administered the beverage 30 min. prior to performing 12 separate tests assessing basic mathematics, simple response, logical reasoning, hand-eye coordination, and spatial and assembly skills. The Spielberger State Anxiety test was administered immediately after consuming the test beverage and once again at posttest. Analysis showed that caffeine did not significantly affect performance on all tests with the exception of the peripheral awareness (hand-eye coordination) test on which performance was higher after ingesting caffeine. The placebo treatment produced no effect on state anxiety, which contrasted with a significant rise in anxiety after caffeine consumption. State anxiety values were significantly greater after caffeine treatment relative to the placebo at pretest, and this difference persisted at posttest. These results demonstrated that the dose of caffeine increased scores on state anxiety for individuals who consumed less than three caffeinated beverages weekly but had very little effect on performance of low intensity tasks, except for a hand-eye coordination test involving peripheral awareness. Perhaps longer continuous performance of more demanding tasks would be more sensitive.  相似文献   
156.
Support groups are rapidly becoming an important part of the recovery process for many people who stutter, and a growing number of speech-language pathologists (SLPs) are encouraging their clients to participate in support groups. At present, however, little is known about the individuals who join stuttering support groups and the benefits they derive from their participation. This study surveyed members of the National Stuttering Association (NSA) to learn about their experiences in support groups, as well as their experiences in speech therapy. Respondents were 71 people who attended the 1999 NSA conference in Tacoma, WA. The majority of respondents had participated in treatment several times during their lives, using a variety of techniques. Respondents who had participated in fluency-shaping treatments were more likely to report that they had experienced a relapse than those who had participated in stuttering modification or combined treatments. Also, there was a strong positive correlation between respondents' satisfaction with treatment and their judgments of clinicians' competence, suggesting that improved training for SLPs should lead to improved treatment for people who stutter. Results will be used to provide a foundation for further evaluations of the benefits of support group participation for people who stutter. EDUCATIONAL OBJECTIVES: The reader will learn (a) that many people who participate in the NSA have had numerous and varied experiences with speech treatment throughout their lives, (b) which aspects of treatment and support group participation are seen as most beneficial for people who participate in the NSA.  相似文献   
157.
In this study, we investigated the Five-factor model in the concurrent prediction of positive symptom schizotypy as measured by the Magical Ideation (Eckblad & Chapman, 1983) and Perceptual Aberration (Chapman, Chapman, & Raulin, 1978) scales and negative symptom schizotypy as measured by the Physical Anhedonia (Chapman, Chapman, & Raulin, 1976) and Revised Social Anhedonia (Eckblad, Chapman, Chapman, & Mishlove, 1982; Mishlove & Chapman, 1985) scales. Previous studies suggest that these measures reflect the core symptoms found in schizotypal and schizoid personality disorder (Bailey, West, Widiger, & Freiman, 1993). Negative symptoms were significantly predicted by Neuroticism (+), Extraversion (-), Openness (-), and Agreeableness (-) domains of the Revised NEO Personality Inventory (NEO-PI-R; Costa & McCrae, 1992). Additionally, positive symptoms were significantly predicted by Neuroticism (+), Openness (+), and Agreeableness (-). In addition, we examined the validity of lower order traits in de- scribing these symptoms of character pathology. These findings lend further support for the use of domain and facet scales of the NEO-PI-R in the identification of personality pathology.  相似文献   
158.
The authors examined emotion-specific patterns of appraisal, coping, and cardiovascular reactivity during real ongoing emotional episodes. In this study, 109 participants performed a neutral opinion-expression task, where a confederate elicited anger, shame, or pride using verbal and nonverbal behavior. The authors assessed cognitive appraisals, emotional reactions, coping, outcomes (state self-esteem and outcome satisfaction), and cardiovascular reactivity. Results indicated substantial and theoretically consistent differences between the 3 emotions (and differences from a nonemotion condition) for cognitive appraisals, self-reported coping, behavioral coping, self-esteem, and cardiovascular reactivity. The results are discussed in relation to their implications for emotion theory and for psychological and physical health. Overall, the results suggest that researchers can study emotion-related issues using authentic emotional reactions.  相似文献   
159.
Functional magnetic resonance imaging has emerged as a powerful tool for mapping the neurologic underpinnings of sensory, motor and cognitive function. Much of this evolution carries assumptions about the subject population under study and, in particular, the neurologic status of subjects entered into studies either as healthy controls or as belonging to a specific disease group. Recent reports of incidental MRI abnormalities in normal volunteers for fMRI studies have brought to attention a variety of practical challenges and ethical dilemmas for researchers, many of whom are not physicians and most of whom have no formal radiological training. We propose a minimum standard for consenting subjects in fMRI protocols, and consider strategies over the longer term that call for expert physician participation, archiving of incidental findings including false positives, and the adoption of guidelines for handling variation in neural activations or performance that appear outside expected norms.  相似文献   
160.
In the first part of this paper we review evidence suggesting that there exists a mechanism that selects input on the basis of its similarity to the required action. This response-based input selection differs from the more established space- and object-based input selection in that it is not constrained by the structure of the input. Our evidence suggests that the two-choice Stroop effect is caused by this response-based selection mechanism. By contrast, it is known that the flanker effect is determined by the space- and object- based selection mechanisms. We explore whether the conflict resolution of the Stroop and flanker tasks is different as well by embedding these two tasks in a PRP (Psychological Refractory Period) paradigm. We show that the Stroop and the PRP effects are additive whereas the flanker and the PRP effects are underadditive, suggesting that the processes in charge of the conflict resolution in the Stroop and the flanker tasks are indeed different. We discuss possible reasons for this difference, and discuss possible ways in which the response-based mechanism can be implemented in information processing models.  相似文献   
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