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51.
Two independent samples of pregnant smokers were interviewed about their cigarette smoking and were tested with biochemical markers at the beginning and end of their pregnancies. Participants were mainly unmarried, racial minorities (chiefly Hispanic), and residents of the inner city. Phi coefficients between self‐reported and chemical indicators ranged from .42 to .74. Contrary to expectations, the self‐report/biochemical‐measure correlations were higher at the end than at the beginning of the pregnancy term. The higher end‐of‐term correspondence between self‐report and chemical indicators likely reflected better reliability of the measures, when taken at term. The results are in accord with earlier research with other populations, indicating adequate validity for self‐reported smoking.  相似文献   
52.
Ellen Lenney 《Sex roles》1981,7(9):905-924
Previous investigators have suggested that women display lower self-confidence than men across almost all achievement situations. The empirical validity of this suggestion is assessed in an experiment testing the following hypotheses: (1) Sex differences in self-confidence depend upon the particular ability area. (2) Women's self-confidence is more influenced than men's by characteristics of the particular individual with whom they compare themselves. Undergraduates completed verbal, interpersonal perceptiveness, spatial-mechanical, and creativity subtests. After each subtest, subjects estimated both their own score and that of the average undergraduate, the average male undergraduate, or the average female undergraduate. Self-confidence was operationally defined in terms of how favorably subjects compared their work to that of their peers. As predicted, women's self-confidence was lower than men's in only the spatial-mechanical and creativity subtests; and for women, but not for men, self-confidence depended upon which peer was specified. It is concluded that situation variables do determine sex differences in self-confidence and that women's self-confidence may be unduly affected by situation-specific comparison cues.The preparation of this article was supported in part by a Doctoral Dissertation Fellowship in Women's Studies awarded to the author by the Woodrow Wilson National Fellowship Foundation. Some portions of the study reported in this article were presented at the Western Psychological Association 1976 Convention (Lenney, Note 1) and were briefly abstracted in another article (Lenney, 1977). The author wishes to express her deep appreciation to Walter Mischel and to Sandra Bem for their invaluable consultations on the writing of this article.  相似文献   
53.
Stage theories are commonly used to represent the structure of cognitive processes in the domains of cognitive processing and cognitive development. Hierarchical unidimensional theories consisting of a single sequence of stages through which development proceeds in one direction only have predominated. However, a review of stage theories revealed that a two-dimensional, interactive (multidimensional) structure is warranted. Particularly in the area of cognitive development, results of research have supported subdivision of the stages of prominent unidimensional theories. Following this trend a small number of theorists have developed multidimensional theories, most of which consist of a sequence of stages in which each stage contains a number of subsidiary stages or levels. The emergence of a similar trend in other domains is examined, and the prospects of using an existing multidimensional framework to enable future comparisons and integration of different stage theories is explored.  相似文献   
54.
55.
This article presents theoretical considerations based on cultural analysis approaches to studying pornography and sexuality as a means of starting to suggest a new agenda for cyberporn research. By bringing to the forefront concepts of how subjectivity and sexuality are produced within the computer/Internet apparatus, I hope to diversify the focus in cyberporn research away from social science approaches and pre-Foucaultian assumptions of the subject which obscure understandings of new media and cyberporn use. Through a summary of visual culture studies and reception studies of pornography, I argue that cyberporn must be understood as contingent within the encoding and decoding processes and discourses of sexuality (Foucault) in which it is produced and consumed. My focus here is the home office/terminal as the site of reception/cyberporn use. While there is potential for a great variety of cultural analytic approaches to the study of cyberporn and how new media use influences sexuality, I end with specific suggestions for researching cyberporn reception in the home. The computer’s allure is more than utilitarian or aesthetic; it is erotic. Instead of a refreshing play with surfaces, as with toys or amusements, our affair with information machines announces a symbiotic relationship and ultimately a mental marriage to technology. Rightly perceived, the atmosphere of cyberspace carries the scent that once surrounded Wisdom. The world rendered as pure information not only fascinates our eyes and minds, but also captures our hearts. We feel augmented and empowered. Our hearts beat in the machines. This is Eros. (Michael Heim, The Metaphysics of Virtual Reality)  相似文献   
56.
The emotional attentional blink (EAB) refers to a temporary impairment in the ability to identify a target when it is preceded by an emotional distractor. It is thought to occur because the emotional salience of the distractor exogenously captures attention for a brief duration, rendering the target unattended and preventing it from reaching awareness. Here we tested the extent to which the EAB can be attenuated by inducing a diffuse top-down attentional state, which has been shown to improve target identification in an analogous attentional phenomenon, the attentional blink. Rapid sequences of landscape images were presented centrally, and participants reported the orientation of a ± 90° rotation of a landscape target. To induce a diffuse state of attention, participants were given a secondary task of monitoring for the appearance of a colored dot in the periphery. We found that emotional distractors impaired target recognition performance to comparable extents, regardless of whether or not participants concurrently performed the peripheral-monitoring task. Moreover, we found that performance of the secondary task led to an impaired ability to ignore neutral distractors. Subjective ratings of target vividness mirrored the behavioral accuracy, with frequent reports of intermediate levels of vividness suggesting that the EAB might impair target visibility in a graded manner. Our results demonstrate that the EAB is robust to manipulations of top-down attention, suggesting that the temporary capture of attention by emotionally salient stimuli involves processes that are distinct from those that produce the attentional blink.  相似文献   
57.
This essay is based on a pilot study that examined the effects of managed care on the treatment of children and families, with special attention to community mental health. We embarked on the pilot study to test the accuracy and generalizability of our impression that family therapy and other systemic practices have been marginalized in ordinary clinics and agencies, and to understand the reasons why. We interviewed managed care providers, researchers, family therapy trainers, and clinicians in the Northeast. Our findings led to seven themes that support our impression that, even though there is a consensus about the need for coordinated family-based services, there is a disconnection between state policies, contractual requirements and what is actually occurring at the implementation level. This study suggests that our knowledge of human systems may be in danger of being disqualified and lost, with damaging consequences for the care of children. Yet, as systemic thinkers and practitioners, it is our belief that ethical and effective treatment need not be at odds with care that is cost-efficient. The direction of our future research will be to study whether the involvement of all stakeholders at all levels of planning and training leads to systemic family-based practices that consistently save costs and provide high-quality care.  相似文献   
58.
Calculating and graphing within-subject confidence intervals for ANOVA   总被引:1,自引:0,他引:1  
The psychological and statistical literature contains several proposals for calculating and plotting confidence intervals (CIs) for within-subjects (repeated measures) ANOVA designs. A key distinction is between intervals supporting inference about patterns of means (and differences between pairs of means, in particular) and those supporting inferences about individual means. In this report, it is argued that CIs for the former are best accomplished by adapting intervals proposed by Cousineau (Tutorials in Quantitative Methods for Psychology, 1, 42–45, 2005) and Morey (Tutorials in Quantitative Methods for Psychology, 4, 61–64, 2008) so that nonoverlapping CIs for individual means correspond to a confidence for their difference that does not include zero. CIs for the latter can be accomplished by fitting a multilevel model. In situations in which both types of inference are of interest, the use of a two-tiered CI is recommended. Free, open-source, cross-platform software for such interval estimates and plots (and for some common alternatives) is provided in the form of R functions for one-way within-subjects and two-way mixed ANOVA designs. These functions provide an easy-to-use solution to the difficult problem of calculating and displaying within-subjects CIs.  相似文献   
59.
Welch’s (Biometrika 29: 350–362, 1938) procedure has emerged as a robust alternative to the Student’s t test for comparing the means of two normal populations with unknown and possibly unequal variances. To facilitate the advocated statistical practice of confidence intervals and further improve the potential applicability of Welch’s procedure, in the present article, we consider exact approaches to optimize sample size determinations for precise interval estimation of the difference between two means under various allocation and cost considerations. The desired precision of a confidence interval is assessed with respect to the control of expected half-width, and to the assurance probability of interval half-width within a designated value. Furthermore, the design schemes in terms of participant allocation and cost constraints include (a) giving the ratio of group sizes, (b) specifying one sample size, (c) attaining maximum precision performance for a fixed cost, and (d) meeting a specified precision level for the least cost. The proposed methods provide useful alternatives to the conventional sample size procedures. Also, the developed programs expand the degree of generality for the existing statistical software packages and can be accessed at brm.psychonomic-journals.org/content/ supplemental.  相似文献   
60.
Køppe’s proposition of four layers in theoretical building are used here in the exploration of a specific case of eclectic combination, the use of Piagetian and Vygotskian general approaches to the analysis of proportional reasoning as a cognitive mathematical ability. It is proposed here that the eclectic consideration of these contributions depends on the consideration of their specificity, in the sense that they highlight different aspects of the phenomenon under scrutiny, and also on the consideration of the coherence between this eclectic convergence and premises in terms of schools of thought under which each contribution is framed. We conclude proposing in accordance to S. Køppe’s proposal that eclecticism can be valuable and heuristic in theory development, but this contribution will depend largely on the effort in establishing careful relations between the four layers of theory-building.  相似文献   
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