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881.
Rules of thumb for power in multiple regression research abound. Most such rules dictate the necessary sample size, but they are based only upon the number of predictor variables, usually ignoring other critical factors necessary to compute power accurately. Other guides to power in multiple regression typically use approximate rather than precise equations for the underlying distribution; entail complex preparatory computations; require interpolation with tabular presentation formats; run only under software such as Mathmatica or SAS that may not be immediately available to the user; or are sold to the user as parts of power computation packages. In contrast, the program we offer herein is immediately downloadable at no charge, runs under Windows, is interactive, self-explanatory, flexible to fit the user’s own regression problems, and is as accurate as single precision computation ordinarily permits. 相似文献
882.
Keith?D.?Huff Yukiko?Asaka Amy?L.?Griffin William?P.?Berg Matthew?A.?Seager Stephen?D.?BerryEmail author 《Integrative psychological & behavioral science》2004,39(1):16-23
Analysis of naturalistic chewing patterns may provide insight into mapping the neural substrates of jaw movement control systems,
including their adaptive modification during the classically conditioned jaw movement (CJM) paradigm. Here, New Zealand White
rabbits were administered food and water stimuli orally to evaluate the influence of stimulus consistency on masticatory pattern.
Chewing patterns were recorded via video camera and movements were analyzed by computerized image analysis. The mandibular
kinematics, specifically the extent of dorsal/ventral, medial/lateral, and rostral/caudal movement, were significantly larger
in food-evoked than water-evoked chewing. Water-evoked chewing frequency, however, was significantly higher than that of food-evoked
movements. In light of known cortical mastication modulatory centers, our findings implicate different neural substrates for
the responses to food and water stimuli in the rabbit. A detailed delineation of jaw movement patterns and circuitry is essential
to characterize the neural substrates of CJM. 相似文献
883.
Despite numerous measures of facets of the body image construct, no single assessment broadly measures a continuum of body image disturbance. Accordingly, this study developed the Body Image Disturbance Questionnaire (BIDQ), derived from the Body Dysmorphic Disorder Questionnaire. Participants were 220 college women and 75 college men who completed an online survey containing this new assessment and established measures of body image and psychosocial functioning. Results confirmed that the Body Image Disturbance Questionnaire was internally consistent and free of impression-management response bias. For both sexes, the measure converged appropriately with other body image indices (evaluation, affect, investment, and impact), was positively correlated with depression, social anxiety, and eating disturbance. Scores on this assessment also predicted psychosocial functioning above and beyond body dissatisfaction as a predictor. Greater body image disturbance was observed among women than men, among heavier than lighter women, and among White than African American women. Limitations and future research implications are discussed. 相似文献
884.
Multiple study trials and judgments of learning 总被引:5,自引:0,他引:5
We compared judgments of learning (JOLs) that were made either (a) after 1 study trial, (b) 2 study trials, or (c) in-between the 1st and 2nd study trials. In regard to the absolute accuracy of JOLs at predicting subsequent recall, we replicated previous findings of an underconfidence-with-practice effect for immediate JOLs and report for the first time a new finding of an underconfidence-with-practice effect for delayed JOLs (i.e., delayed JOLs after one trial overestimated the likelihood of subsequent recall, whereas delayed JOLs after two trials underestimated that likelihood). Also, although delayed JOLs always had a greater relative accuracy than did immediate JOLs, the relative accuracy of immediate and delayed JOLs was approximately the same after 1 versus 2 study trials. These results demonstrate that additional study trials affect the absolute accuracy of all JOLs but not the relative accuracy of any JOLs. Thus an increase in the number of study trials produced an increasing bias to be underconfident about the subsequent likelihood of recall but did not affect people's ordering of which items had been more (versus less) well-learned. 相似文献
885.
This study examined the relationship between biological and social risk factors and aggressive behavior patterns in an Australian high-risk sample of 370 adolescents. Perinatal, temperamental, familial, sociodemographic, and behavioral data were collected during interviews completed during pregnancy. immediately postpartum, and when the children were 6 months old and 5, 14, and 15 years old. Youths were given tests of verbal and neuropsychological functioning at the age 5 and age 15 follow-ups. Youths were divided into early-onset persistent aggression, adolescent-onset aggression, and nonaggressive behavior groups. Results revealed that the interaction of biological and social risk factors was significantly related to early-onset persistent aggression. Gender and developmental phase of measurement moderated the relationship between biosocial risks and the outcomes of early-onset persistent aggression and adolescent-onset aggression. 相似文献
886.
The role of the shared family context in differential parenting 总被引:6,自引:0,他引:6
This article examines the role of the shared family context in understanding differential parental treatment of children. Child-specific and family-context predictors of differential parental positivity and negativity were examined using multilevel modeling in a population of 8,476 children nested in 3,762 families. Child age was the strongest child-specific predictor of positivity and differential positivity. Lower socioeconomic status (SES), marital dissatisfaction, and larger family size were associated with higher levels of differential positivity. There was evidence of potentiation when risks were combined. Children's temperament was associated with parental negativity and differential negativity. The strength of this association was moderated by SES. Mixed-gender sibships in families with marital dissatisfaction and children in single-parent families received the highest levels of differential negativity. The findings are discussed in the context of shared and nonshared environmental influences on development. 相似文献
887.
Joel Thomas Tierno 《International Journal for Philosophy of Religion》2003,54(3):199-199
Authors Index
List of Contributors Volume 54 相似文献888.
In this article, the authors assessed whether continuously scaled symptom parameters derived from growth models (T. M. Piasecki et al., 2003) are linked to smoking at long-term follow-up by using data from a large-scale clinical trial (N = 893). Results revealed that higher withdrawal intercepts, positive linear slopes, and greater volatility were all positively associated with relapse, and cigarette coefficients (indicating smoking-induced withdrawal reduction) were negatively related to relapse. In models keyed around the first lapse to smoking, those destined to lapse reported more severe withdrawal during abstinence, and withdrawal patterns discriminated groups defined according to lapse duration. The findings complement earlier heterogeneity studies in implicating the pattern of changing withdrawal symptoms over time as a factor strongly associated with smoking relapse. 相似文献
889.
Longitudinal analysis of flexibility and reorganization in early adolescence: a dynamic systems study of family interactions 总被引:1,自引:0,他引:1
A dynamic systems (DS) approach was used to study changes in the structure of family interactions during the early adolescent transition period. Longitudinal observational data were collected in 5 waves prior to, during, and after the transition. Boys (n = 149 families) were videotaped problem solving with their parents at 9-10 years old and every 2 years thereafter until they were 18 years old State space grids (a new DS method) were constructed for all families across all waves. Two variables indexing the variability of the family interactions were derived from the grids. As hypothesized, the DS variables revealed a significant quadratic effect related to a peak in variability at 13-14 years of age. 相似文献
890.
Critchfield TS Haley R Sabo B Colbert J Macropoulis G 《Journal of applied behavior analysis》2003,36(4):465-486
It has been suggested that the work environment of the United States Congress bears similarity to a fixed-interval reinforcement schedule. Consistent with this notion, Weisberg and Waldrop (1972) described a positively accelerating pattern in annual congressional bill production (selected years from 1947 to 1968) that is reminiscent of the scalloped response pattern often attributed to fixed-interval schedules, but their analysis is now dated and does not bear on the functional relations that might yield scalloping. The present study described annual congressional bill production over a period of 52 years and empirically evaluated predictions derived from four hypotheses about the mechanisms that underlie scalloping. Scalloping occurred reliably in every year. The data supported several predictions about congressional productivity based on fixed-interval schedule performance, but did not consistently support any of three alternative accounts. These findings argue for the external validity of schedule-controlled operant behavior as measured in the laboratory. The present analysis also illustrates a largely overlooked role for applied behavior analysis: that of shedding light on the functional properties of behavior in uncontrolled settings of considerable interest to the public. 相似文献