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701.
PMETRIC is a computer program for the analysis of observed psychometric functions. It can estimate the parameters of these functions, using either probit analysis (a parametric technique) or the Spearman-K?rber method (a nonparametric one). For probit analysis, either a maximum likelihood or a minimum chi 2 criterion may be used for parameter estimation. In addition, standard errors of parameter estimates can be estimated via bootstrapping. The program can be used to analyze data obtained from either yes-no or m-alternative forced-choice tasks. To facilitate the use of PMETRIC in simulation work, an associated program, PMETGEN, is provided for the generation of simulated psychometric function data. Use of PMETRIC is illustrated with data from a duration discrimination task.  相似文献   
702.
703.
The precision of an eye-tracker is critical to the correct identification of eye movements and their properties. To measure a system’s precision, artificial eyes (AEs) are often used, to exclude eye movements influencing the measurements. A possible issue, however, is that it is virtually impossible to construct AEs with sufficient complexity to fully represent the human eye. To examine the consequences of this limitation, we tested currently used AEs from three manufacturers of eye-trackers and compared them to a more complex model, using 12 commercial eye-trackers. Because precision can be measured in various ways, we compared different metrics in the spatial domain and analyzed the power-spectral densities in the frequency domain. To assess how precision measurements compare in artificial and human eyes, we also measured precision using human recordings on the same eye-trackers. Our results show that the modified eye model presented can cope with all eye-trackers tested and acts as a promising candidate for further development of a set of AEs with varying pupil size and pupil–iris contrast. The spectral analysis of both the AE and human data revealed that human eye data have different frequencies that likely reflect the physiological characteristics of human eye movements. We also report the effects of sample selection methods for precision calculations. This study is part of the EMRA/COGAIN Eye Data Quality Standardization Project.  相似文献   
704.
This study investigated the relationship between physical and mental health and psychosocial variables and recent (within the last 12 months) mental health service use among 240 medical patients recruited from general and specialty outpatient clinics at an academic medical center. Results indicated 43.3% of the participants had recently received mental health services in the form of psychotropic medication (75%), psychotherapy (2%), or a combination of these treatments (20.2%). Among patients with moderate to severe symptoms of anxiety or depression, approximately two-thirds were receiving mental health treatment. Moreover, four variables (healthcare provider referral for mental health services, perceived need for mental health services, prior use of mental health services, and frequency of medical appointments) were significant unique predictors of recent mental health service use. This suggests collaborative/integrated medical care may increase needed mental health service use.  相似文献   
705.
ABSTRACT— Little is known about the associations between premenstrual depressive symptoms and specific physical symptoms of the menstrual cycle. In a nonclinical sample of 183 female university students, six physical symptoms of the menstrual cycle (headaches, skin changes, gastrointestinal problems, breast changes, and coagulation and heaviness of menstrual bleeding) were tested for their associations with premenstrual depressive symptoms. The physical symptoms explained nearly 30% of the variance in depressive symptoms. Moreover, when the summed score for all six physical symptoms was used as a predictor of depressive symptoms, a strong linear effect and a moderate curvilinear effect were observed. These results could not be explained by response bias or by the presence of a small group of highly depressed individuals. This study emphasizes the need to consider physical symptoms of the menstrual cycle to better understand premenstrual depressive symptoms, and suggests that the contribution of the menstrual cycle to depressive symptoms in the general population is underrecognized.  相似文献   
706.
The present study investigated the relevance of the “aspiration–expectation gap” and traditional gender differences among urban youth in middle school and high school (N = 294). Results failed to indicate a significant difference between the occupational prestige levels of aspired and expected careers, but did indicate a significant difference between aspired and expected levels of education. In general, the proportion of girls significantly outweighed the proportion of boys in traditionally “masculine” occupations with high levels of prestige; girls also had higher levels of occupational prestige than boys in terms of careers they hoped and expected to obtain. Black and bi/multi-racial youth expected to have higher levels of education than White youth.  相似文献   
707.
In this study, two longitudinal models of early adolescent risky sexual behaviors (RSB) were compared using a pooled sample of 267 Canadian and Italian adolescents (55% females; 53% Canadians) assessed yearly from grade 8 to 10. We focused on parenting practices (monitoring, control, limit setting), adolescent problem behaviors (antisocial behaviors, substance use) and their friends' deviance (antisocial behaviors, substance use) as predictors of condom use frequency and lifetime number of sexual partners. The socialization model postulates that youths' problem behaviors and RSB are behaviors learned within the friendship network where deviancy training can occur. The selection model posits that delinquent youth tend to affiliate with each other, and that RSB is one of many behaviors that can form the basis of selection. Using structural equation modeling, this study showed that the socialization model was the most accurate to explain the emergence of RSB. A full mediation of parenting practices, passing through deviant friends and youths' problem behavior, was observed for condom use. The same process applied to number of sexual partners, but a direct effect for parenting practices was also found.  相似文献   
708.
Current measures assessing older adults' functional ability detect existing limitations on essential tasks rather than changes in other aspects of functioning that could indicate future limitations. The perceived motor‐efficacy scale was developed to measure capability beliefs of healthy older adults across a range of daily action tasks. Subscales were developed through interviews with older volunteers and academics, then administered to participants aged 60–96 (N=300). Factor analysis of subscale scores produced 10 subscales. These demonstrated strong internal reliability, which was replicated with a second sample aged 60–92 (N=167). The influence of perceived motor‐efficacy on performance of cognitively demanding action tasks was investigated with a third sample aged 60–88 (N=134). On a task assessing the inhibition of an inappropriate action, older adults in their 80s with high confidence produced minor errors, whereas those with lower confidence produced extreme errors. On another task assessing the ability to inhibit a previously learnt action, those with high levels of perceived motor‐efficacy performed better amongst those least able to inhibit, but more poorly among those most able. Perceived motor‐efficacy may therefore be useful in identifying older adults at risk of functional limitations and enabling interventions before the onset of illness.  相似文献   
709.
Social scientific investigation into the religiospiritual characteristics of American Indians rarely includes analysis of quantitative data. After reviewing information from ethnographic and autobiographical sources, we present analyses of data from a large, population-based sample of two tribes (n = 3,084). We examine salience of belief in three traditions: aboriginal, Christian, and Native American Church. We then investigate patterns in sociodemographic subgroups, determining the significant correlates of salience with other variables controlled. Finally, we examine frequency with which respondents assign high salience to only one tradition (exclusivity) or multiple traditions (nonexclusivity), again investigating subgroup variations. This first detailed, statistical portrait of American Indian religious and spiritual lives links work on tribal ethnic identity to theoretical work on America's "religious marketplace." Results may also inform social/behavioral interventions that incorporate religiospiritual elements.  相似文献   
710.
Mizuko kuyō, the popular Japanese Buddhist memorial service for aborted fetuses, has been increasingly appropriated by both sides of the contentious American abortion debate. In the wake of exposure to the idea of mizuko kuyō, both pro-life and pro-choice Buddhist appropriators resort to discussions of the ritual because they feel it helps them strengthen the weaknesses of their own sides and undermine the positions of their opponents. Pro-life Americans use mizuko kuyō to prove that they care about women, not just fetuses, and that their convictions do not arise simply out of private religious feelings but objective psychological and medical facts. Pro-choice Americans, on the other hand, use mizuko kuyō to demonstrate that they care about families and children, not just women, and that they are sensitive not only to the secular but also the religious aspects of life and abortion. In the process, pro-life Christians, who seem to be primarily motivated by their exclusivist and authoritarian Biblical convictions, turn for support to a non-theistic religion they otherwise oppose; pro-choice feminists, who seem to have chiefly secular reasons for supporting abortion rights, turn for support to a supernatural entity and his retinue of angry fetal ghosts.  相似文献   
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