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881.
882.
The efficacy of three different schedules of reinforcement for promoting and sustaining drug abstinence was compared in this study. Cigarette smoking was studied as an exemplar of stimulant drug self-administration. Sixty cigarette smokers were assigned to one of three groups (progressive rate of reinforcement, fixed rate of reinforcement, and yoked control). Participants in all three groups were asked to refrain from smoking for 1 week. Participants in the progressive and fixed groups achieved greater mean levels of abstinence than those in the control group. Participants in the progressive group were significantly less likely to resume smoking when they became abstinent than participants in the other groups.  相似文献   
883.
“Epidemic” models of transitions between stages of cigarette smoking describe the spread of smoking behavior through face-to-face encounters. An epidemic model was successfully fitted that allowed epidemic parameters to be conditioned on the smoking status of adolescents' parents. Model comparisons supported the conclusion that the transition from nonsmoker to trier involved social contacts, whereas the transition from trier to regular smoker was best modeled as a constant rate (i.e., did not depend on the population prevalence of smokers). The transition rate from nonsmoker to trier was more rapid in children of smoking parents than in children of nonsmoking parents. Adolescents with and without smoking parents did not differ in the rate of transition from trier to regular smoking.  相似文献   
884.
Results from two investigations examine the relationship between problem solving strategies (leaping and flexibility) and measures of insight and scholastic aptitude. In Study 1, university students were asked to use minimal information to solve perceptual and linguistic items on a clue-efficiency task. Results reveal a significant relationship between both leaping and insight scores and flexible-leaping and scores on the quantitative subtest of the SAT. A second study examined the developmental trajectory of flexibility, leaping, and clue-efficiency. Developmental declines, notably between fifth and sixth grades, are reported in the use of flexibility and leaping. These developmental declines do not result from shifts to more sophisticated (e.g., efficient) strategies, as no developmental differences in efficiency were observed.  相似文献   
885.
Members of the Association for Counselor Education and Supervision completed a questionnaire on career satisfaction. A majority reported being quite satisfied with their careers. Most experienced only occasional burnout, and over half perceived their career stress as no greater than moderate.  相似文献   
886.
887.
The purpose of this study was (a) to evaluate the ability of the existing validity indices of the Minnesota Multiphasic Personality Inventory (MMPI-2) in detecting faking. bad and faking-good profiles, (b) to differentiate between two strategies for faking-good (denial and claiming extreme virtue), (c) to determine the effectiveness of the new MMPI-2 validity scale, the S scale, in detecting people's tendency to present themselves in a superlative manner, and (d) to explore the response strategy under conditions in which individuals we known to be distorting their responses to the MMPI-2 Participants were 167 undergraduate, college students who were administered the test under different conditions, and 50 hospitalized, psychiatric patients. Mean profile configurations and optimal cutoff scores obtained in this study were similar to those reported in previous studies. Accurate identification of faked profiles was achieved. The new S scale and its subscales, especially S2 (Serenity), S3 (Contentment With Life), and S5 (Denial of Moral Flaws), showed particular promise in detecting faking-good (denial and claiming extreme virtue) profiles, Participant's debriefing provided valuable information about the participants' understanding of the instructions and their deception strategies. The attempts to differentiate between two strategies for faking-good, denial and claiming extreme virtue, were not successful, However, these results should not be taken to indicate that the particular strategies assessed in this study cannot be differentiated. Methodological issues reviewed suggest that further research might yield more understanding of the nature of any deception efforts made by respondents. In addition, future, research is needed to discover if the findings from this study generalize to other clinical settings and populations.  相似文献   
888.
Archer and Krishnamurthy (1993a, 1993b) systematically reviewed the Minnesota Multiphasic Personality Inventory (MMPI)-Rorschach research and found that there is minimal if any association between the two tests. In response to this review, data are reported demonstrating a positive association between various Rorschach variables and objective criteria. Data gleaned from published and yet unpublished sources suggest that the Rorschach is related to various self-report, other-report, and behavioral criteria, with children and adults, for psychosis and other constructs. Data are also presented suggesting that part of the disagreement between the two tests may be due to different types of response bias and positive self-presentations on the two tests. Research findings pertinent to differential validity as a function of the number of Rorschach responses protocol are also explored. I conclude with research recommendations regarding test-specific understandings of response bias and Rorschach protocol complexity as a moderator variable.  相似文献   
889.
890.
We develop simple noniterative estimators of the polyserial correlation coefficient. A general relationship between the polyserial correlation and the point polyserial correlation is exploited to give extensions of Pearson's, Brogden's, and Lord's biserial estimators to the multicategory setting. The small sample and asmptotic properties of these estimators are studied in some detail. A comparison with maximum likelihood estimates shows that Lord's polyserial estimator is fairly efficient across three probability models.The authors would like to thank the referees for suggestions that improved the presentation of the paper.  相似文献   
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