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271.
Self-rated general health has been used widely in health surveys as a single-item measurement of health-rated quality of life. Heterogeneity in self-evaluation of health has been well documented, yet the causes of this heterogeneity are poorly understood. This study evaluated the moderating effects of age, aging, gender, race, education and income on the relationship between physical functioning and self-rated general health using social comparison theory as a guiding framework. A longitudinal mixed-effects regression model was used to analyze a cohort enrolled into the Health and Retirement Study in 1993 that was interviewed at baseline and during four subsequent waves. The results revealed that the association between physical functioning and self-rated general health is weaker among subgroups that tend to have lower health status; i.e., older individuals, non-Caucasians and less educated individuals. These findings suggest the usefulness of social comparison theory in explaining self-rated general health and provide the basis for future research.  相似文献   
272.
Bugden S  Ansari D 《Cognition》2011,118(1):32-44
In recent years, there has been an increasing focus on the role played by basic numerical magnitude processing in the typical and atypical development of mathematical skills. In this context, tasks measuring both the intentional and automatic processing of numerical magnitude have been employed to characterize how children’s representation and processing of numerical magnitude changes over developmental time. To date, however, there has been little effort to differentiate between different measures of ‘number sense’. The aim of the present study was to examine the relationship between automatic and intentional measures of magnitude processing as well as their relationships to individual differences in children’s mathematical achievement. A group of 119 children in 1st and 2nd grade were tested on the physical size congruity paradigm (automatic processing) as well as the number comparison paradigm to measure the ratio effect (intentional processing). The results reveal that measures of intentional and automatic processing are uncorrelated with one another, suggesting that these tasks tap into different levels of numerical magnitude processing in children. Furthermore, while children’s performance on the number comparison paradigm was found to correlate with their mathematical achievement scores, no such correlations could be obtained for any of the measures typically derived from the physical size congruity task. These findings therefore suggest that different tasks measuring ‘number sense’ tap into different levels of numerical magnitude representation that may be unrelated to one another and have differential predictive power for individual differences in mathematical achievement.  相似文献   
273.
Six pigeons were trained in a change detection task with four colors. They were shown two colored circles on a sample array, followed by a test array with the color of one circle changed. The pigeons learned to choose the changed color and transferred their performance to four unfamiliar colors, suggesting that they had learned a generalized concept of color change. They also transferred performance to test delays several times their 50-msec training delay without prior delay training. The accurate delay performance of several seconds suggests that their change detection was memory based, as opposed to a perceptual attentional capture process. These experiments are the first to show that an animal species (pigeons, in this case) can learn a change detection task identical to ones used to test human memory, thereby providing the possibility of directly comparing short-term memory processing across species.  相似文献   
274.
In an investigation of students’ prejudicial biases against instructors who smoke, 61 female and 16 male undergraduates watched and listened to a 20-min lecture about parasomnias, completed a survey asking for instructor evaluation ratings and ratings of perceived learning, and completed a lecture-retention test with multiple-choice questions to assess actual learning. In a between-subjects design, the lecture was given by either a man or woman, who was portrayed as a smoker or nonsmoker. The instructors’ sex and smoking status did not affect the students’ perceived or actual learning (all p’s > .05). However, a significant interaction on the instructor evaluation ratings revealed that students rated the female instructors equivalently (p = .78), but rated the smoker male instructor significantly lower than the nonsmoker male instructor (p = .01). These findings suggest that students hold prejudicial biases against male instructors who smoke, but that these biases do not affect student learning.  相似文献   
275.
The kappa coefficient is one of the most widely used measures for evaluating the agreement between two raters asked to assign N objects to one of K nominal categories. Weighted versions of kappa enable partial credit to be awarded for near agreement, most notably in the case of ordinal categories. An exact significance test for weighted kappa can be conducted by enumerating all rater agreement tables with the same fixed marginal frequencies as the observed table, and accumulating the probabilities for all tables that produce a weighted kappa index that is greater than or equal to the observed measure. Unfortunately, complete enumeration of all tables is computationally unwieldy for modest values of N and K. We present an implicit enumeration algorithm for conducting an exact test of weighted kappa, which can be applied to tables of non‐trivial size. The algorithm is particularly efficient for ‘good’ to ‘excellent’ values of weighted kappa that typically have very small p‐values. Therefore, our method is beneficial for situations where resampling tests are of limited value because the number of trials needed to estimate the p‐value tends to be large.  相似文献   
276.
Schizotypal personality disorder (SPD) is characterized by eccentric behavior and perceptual distortions that closely resemble the patterns observed in those with schizophrenia. Schizophrenia and related personality disorders (i.e., SPD) are associated with deficits in sustained attention, slower than normal reaction times, and manifestations of working memory deficits and erratic cognitive tasks. The present study used the schizotypal personality scale (STA) to compare cognitive abilities of self-reported low schizotypic tendency subjects with high schizotypic tendency subjects. The group scores on the STA differed significantly. Those with high STA scores also tended to have higher state and trait anxiety scores based on the State-Trait Anxiety Inventory (STAI). The groups did not significantly differ on any of the demographic variables tested, including age, education, self-rated health status, and medication. Along with an executive function test, two computerized tasks tested subjects on reaction time and memory. Even when covariates (i.e., state, trait anxiety scores) were analyzed, there were no significant differences between the groups and tasks, although the gathered data showed trends in the expected direction.  相似文献   
277.
This study examined age-related effects of individual DSM criteria for borderline personality disorder (BPD) and symptoms of depression and anxiety in three groups: patients diagnosed with BPD, another personality disorder, or no personality disorder. The goal was to determine if distinctive age effects emerged within the BPD group. This mixed clinical and community sample (N = 380) ranged from 20-50 years old. Each participant was assessed for symptoms of axis I and II psychopathology. We found significant interactions for personality disorder group x age for the suicidal behavior and impulsivity criteria that reflected distinctive changes in the BPD group. The BPD group reported significantly more anxious and depressive symptoms. However, no main effect for age or personality disorder x age interaction emerged with symptoms. These results demonstrate that older individuals with BPD report less impulsivity and fewer suicidal behaviors, although symptoms of distress persist.  相似文献   
278.
Schizotypal personality disorder (SPD) is characterized by eccentric behavior and perceptual distortions that closely resemble the patterns observed in those with schizophrenia. Schizophrenia and related personality disorders (i.e., SPD) are associated with deficits in sustained attention, slower than normal reaction times, and manifestations of working memory deficits and erratic cognitive tasks. The present study used the schizotypal personality scale (STA) to compare cognitive abilities of self-reported low schizotypic tendency subjects with high schizotypic tendency subjects. The group scores on the STA differed significantly. Those with high STA scores also tended to have higher state and trait anxiety scores based on the State-Trait Anxiety Inventory (STAI). The groups did not significantly differ on any of the demographic variables tested, including age, education, self-rated health status, and medication. Along with an executive function test, two computerized tasks tested subjects on reaction time and memory. Even when covariates (i.e., state, trait anxiety scores) were analyzed, there were no significant differences between the groups and tasks, although the gathered data showed trends in the expected direction.  相似文献   
279.
280.
We examined parents’ knowledge, attitudes, and information sources regarding Attention-Deficit/Hyperactivity Disorder (ADHD), including treatment with stimulant medication and behavioral interventions. Responses from parents with a child diagnosed with ADHD and parents without a child diagnosed with ADHD were also compared. Participants consisted of 146 parents of elementary age children from Wisconsin. The surveyed parents were aware of issues surrounding ADHD and the use of stimulant medication, but there were several areas where they possessed inaccurate or incomplete factual information. Parents who had a child diagnosed with ADHD rated the effects of stimulant medication more positively and side effects as less severe than other parents. They also rated behavioral interventions as less effective on all questions. Implications of the study are discussed.  相似文献   
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