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81.
This study examines the relationships between employment status and women's attitudes toward and participation in a higher status voluntary service organization. Data were gathered in 1975 and 1992 from a sample of chapters of the International Association of Women (a pseudonym). The 1992 sample included three percent who reported a racial or ethnic identification other than white. Drawing on several theoretical perspectives, we expected to find differences in the attitudes and level of participation of employed versus non-employed members that would have important effects on organizational functioning. However, few differences in the attitudes of members employed full time, part time, and not in the labor force were found in either 1975 or 1992. There were, however, differences in behavior. Employed members reported spending much less time on organizational activities and were less likely to assume leadership roles, but these differences diminished between 1975 and 1992 as employed women became numerically dominant in the organization, suggesting that the growing presence of employed women in IAW led to the development of informal norms and new policies about the amount of time members should devote to the organization and a corresponding loss in the total number of volunteer hours devoted to it.  相似文献   
82.
Retest stability of DSM-III-R diagnoses was assessed using the DISC-2.1C with a sample of Anglo, African, and Hispanic American adolescent patients 12 to 17 years of age. Based on the kappa statistic, retest stability was fair for any disorder ( =.50), for any anxiety disorder ( =.44), for any affective disorder ( =.53), for any disruptive behavior disorder ( =.58), and for substance use disorders ( =.46). Although there was a trend for reliability to be somewhat higher for African Americans ( =.58) than for Anglos ( =.42) or Hispanics ( =.49), these differences were not statistically significant. In general, 15- to 17-year-olds had somewhat better reliability ( =.58) than did 12- to 14-year-olds ( =.44). Males had somewhat higher reliability ( =.63) than females ( =.43). These findings are congruent with those reported recently using the DISC-R (Schwab-Stone et al., 1993) and suggest that the DISC appears to be at least as reliable as other available child diagnostic instruments. In view of the fair-to-moderate levels of reliability of these instruments in general, future research should focus on the joint effects of instrument, subject, interviewer, and nomenclature on operating characteristics of diagnostic interview schedules, focusing in particular on factors affecting accurate recall and reporting of symptoms and episodes. This research was supported in part by grants MH44214 and MH44773 from the National Institute of Mental Health, and by the Hogg Foundation for Mental Health. The authors wish to acknowledge the participation and collaboration of A. J. Pumariega, J. W. Swanson, and C. E. Holzer III and staff of the Center for Cross-Cultural Research, directed by F. M. Treviño.  相似文献   
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Four ways to reduce scientific errors are by tests of equipment and programs, examination of results, peer review, and replication. This article describes various types of errors that may occur and procedures available for the prevention and correction of both unintentional and intentional errors in experiments that use computer programs to generate the stimuli, record the responses, or analyze the data. We describe a case study of a particular experiment that produced a result that has been found to be erroneous. The case study provides additional evidence of the essential importance of replication for the identification and elimination of scientific error.  相似文献   
86.
Ten subjects served as their own controls in two conditions of continuous, centrifugally produced hypergravity (+2 Gz) and a 1-G control condition. Before and after exposure, open-loop measures were obtained of (1) motor control, (2) visual localization, and (3) hand-eye coordination. During exposure in the visual feedback/hypergravity condition, subjects received terminal visual error-corrective feedback from their target pointing, and in the no-visual feedback/hypergravity condition they pointed open loop. As expected, the motor control measures for both experimental conditions revealed very short lived underreaching (the muscle-loading effect) at the outset of hypergravity and an equally transient negative aftereffect on returning to 1 G. The substantial (approximately 17°) initial elevator illusion experienced in both hypergravity conditions declined over the course of the exposure period, whether or not visual feedback was provided. This effect was tentatively attributed to habituation of the otoliths. Visual feedback produced a smaller additional decrement and a postexposure negative aftereffect, possible evidence for visual recalibration. Surprisingly, the target-pointing error made during hypergravity in the no-visual-feedback condition was substantially less than that predicted by subjects’ elevator illusion. This finding calls into question the neural outflow model as a complete explanation of this illusion.  相似文献   
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Cornell University Medical College, Westchester Division, The New York Hospital, White Plains, New York It is well established that there is a complex timekeeping mechanism in the human brain. This mechanism is associated with a variety of physiological and psychological rhythms having a period of about a day, and thus referred to as circadian rhythms. The circadian system has recently been modeled in terms of two underlying oscillators, one much more resistant to changes in routine than the other. These oscillators are considered to be endogenous, that is, internal to the organism, and not reliant for their existence upon changes in the person’s environment or general behavior. They thus continue to run even when the sleep/wake cycle is suspended, as in sustained operations. Thus, by their very nature, sustained operations require the individual to override the inputs that are coming from his or her circadian system (especially the indication that sleep is required). The aim of this paper is to provide a background to the area of circadian rhythms research, including a section on the methodology, so that the impact of the circadian system on sustained operations can be better understood.  相似文献   
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Two factors, level of processing (Craik & Lockhart, 1972) and congruity (Schulman, 1974), known to have large effects on the recall of experimenter-provided responses to questions, were examined in a series of five incidental learning experiments using subject-generated responses. The data show that manipulation of level of processing has the same effect on recall of subjectgenerated responses as it does on experimenter-provided responses. However, the effect of congruity is reversed for subject-generated responses. The data suggest that the difficulty of generating unrelated responses (“incongruous“ items) may account, at least in part, for the failure of the “principle of congruity“ with subject-generated responses.  相似文献   
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