297 resultados para Dempster-shafer
Resumo:
Aim The aim of this study was to examine the relationship between obesity and self-esteem in children in relation to specific domains of their self-perception, and further to explore the extent to which this may vary by gender and economic circumstances. Method A total of 211 children aged 8–9 years drawn from both advantaged and disadvantaged areas of Belfast completed the Harter Self-Perception Profile for Children and measures of body mass index were obtained. Results Overweight, impoverished children had significantly reduced social acceptance and physical competence scores. Boys had significantly lower scores than girls in the behavioural conduct domain. Girls had significantly lower scores than boys for the athletic competence. Conclusion These results suggest that risk factors of increased weight and impoverished backgrounds have a combined negative effect, placing some children at increased risk of having lower self-perceptions in some, but not all domains. Health interventions for childhood obesity should consider the likelihood of specific relationships between physical and psychosocial factors.
Resumo:
Objective To determine medical students’ self awareness and ability to discriminate right from left; to identify characteristics associated with this ability; and to identify any techniques used to aid discrimination. Design Questionnaire and psychometric study. Setting Undergraduate medical school, Northern Ireland. Participants 290 first year undergraduate students. Main outcome measure Medical students’ ability to discriminate right from left using the Bergen right-left discrimination test. Results Test scores ranged from 31 to 143 on a scale of 0- 144 (mean 112 (standard deviation 22.2)). Male students significantly outperformed female students (117.18 (26.96) v 110.80 (28.94)). Students who wanted to be surgeons performed significantly better than those who wanted to be general practitioners or medical doctors (119.87 (25.15) v 110.55 (27.36) v 112.50 (26.88)). The interaction effect for sex and career wishes was not significant (P=0.370). Students who used learnt techniques to help them discriminate scored significantly less than those who did not (P
Resumo:
Background: The Common Sense Model (CSM) of illness representations was used in the current study to examine the relative contribution of illness perceptions and coping strategies in explaining adjustment to inflammatory bowel disease (IBD). Methods: Participants were 80 adults consecutively attending an outpatients' clinic with a diagnosis of either Crohn's disease or ulcerative colitis. Respondents completed and returned a questionnaire booklet that assessed illness perceptions, coping, and adjustment. Adjustment was measured from the perspectives of psychological distress, quality of life, and functional independence. Results: Illness perceptions (particularly perception of consequences of IBD) were uniformly the most consistent variables explaining adjustment to IBD. Coping did not significantly add to predicting adjustment once illness perceptions were controlled for and therefore did not mediate the relationship between illness perceptions and adjustment, as proposed in the CSM. Conclusions: The results suggest the importance of addressing illness perceptions in developing appropriate psychological interventions for IBD.
Resumo:
Anxiety, negative attitudes, and attrition are all issues presented in the teaching of statistics to undergraduates in research-based degrees regardless of location. Previous works have looked at these obstacles, but none have consolidated a multilingual, multinational effort using a consistent method. Over 400 Spanish-, English-, and German-speaking undergraduate students enrolled in introductory psychology statistics courses were given the Composite Survey of Statistics Anxiety and Attitudes to determine the precursors and effects of existing problems. Results indicated that student background was heavily linked to attitudes and anxieties. The measure was supported as a viable method for more than one class or university in addressing issues in statistics education, developing interventions to improve students’ experiences, and then determining the success of those changes.
Resumo:
Within undergraduate psychology courses, students often have significant levels of anxiety and negative attitudes toward the statistical element. This has been attributed to poor interaction with teachers, fears about mathematical abilities, and simply being unaware of that portion of the course or its relevance to psychology. To address this, 196 undergraduate psychology students completed a survey on statistics anxiety and attitudes. Additionally, 27 different students in similar situations took part in focus group to share their experiences of introductory statistics courses. Survey results showed that fewer than half were aware of the statistics portion of their course and that the expectation was a key factor in their experiences. Qualitative feedback from the focus groups revealed much about how the teaching may or may not improve attitudes nor decrease anxiety. Findings support various broad strategies (i.e. increase awareness of statistics in psychology and confidence in success in the course) as opposed to skill-specific (better ways of teaching probability or using games to increase participation, for example) classroom interventions to improve statistics education.
Resumo:
Aim/Background Psychological models of behaviour change have been found to be useful in predicting health-related behaviour in patients but have rarely been used in relation to the health behaviour of staff. This study explored the association between a range of psychological variables and self-reported handwashing in a sample of nurses who work in a large general hospital. Method A questionnaire-based cross-sectional, correlational study was used. Questionnaires examining demographics, self-efficacy, perceived importance of handwashing, perception of risk, occupational stress and training related to handwashing were administered to an opportunity sample (n = 76) of nurses drawn from an acute hospital. ANOVAs, correlation and regression analyses were performed to determine significant covariates of handwashing behaviour. Findings There was a weak relationship between demographic variables and self-reported handwashing. The degree to which employees perceived their workplace to assist handwashing and perceived importance of handwashing were related to self-reported handwashing. Accordingly further covariates of these variables were sought. Training received and occupational stress both covaried with nurses’ perceptions of the degree to which their workplace assisted handwashing. Nurses’ beliefs regarding the transmission of infections covaried with perceived importance of handwashing. Conclusion Occupational stress was observed to reduce the perception of having a supportive employer: organisations need to facilitate handwashing and protect staff from factors that have a detrimental impact, such as work-related stress. Nurses’ perceived importance of the potential for poor handwashing practice to contribute to the transmission of infections should be highlighted in interventions.
Resumo:
In many domains when we have several competing classifiers available we want to synthesize them or some of them to get a more accurate classifier by a combination function. In this paper we propose a ‘class-indifferent’ method for combining classifier decisions represented by evidential structures called triplet and quartet, using Dempster's rule of combination. This method is unique in that it distinguishes important elements from the trivial ones in representing classifier decisions, makes use of more information than others in calculating the support for class labels and provides a practical way to apply the theoretically appealing Dempster–Shafer theory of evidence to the problem of ensemble learning. We present a formalism for modelling classifier decisions as triplet mass functions and we establish a range of formulae for combining these mass functions in order to arrive at a consensus decision. In addition we carry out a comparative study with the alternatives of simplet and dichotomous structure and also compare two combination methods, Dempster's rule and majority voting, over the UCI benchmark data, to demonstrate the advantage our approach offers. (A continuation of the work in this area that was published in IEEE Trans on KDE, and conferences)
Resumo:
Aim. This paper is a report of a study to test the proposed factor structure of the Index of Sources of Stress in Nursing Students. Background. Research across many countries has identified a number of sources of distress in nursing students but little attempt has been made to understand and measure sources of eustress or those stressors likely to enhance performance and well-being. The Index of Sources of Stress in Nursing Students was developed to do this. Exploratory factor analysis suggested a three-factor structure, the factors being labelled: learning and teaching; placement-related and course organization. It is important, however, to subject the instrument to confirmatory factor analysis as a further test of construct validity. Method. A convenience sample of final year nursing students (n = 176) was surveyed in one university in Northern Ireland in 2007. The Index of Sources of Stress in Nursing Students, which measures sources of stress likely to contribute to distress and eustress, was completed electronically. The LISREL programme was used to carry out the confirmatory factor analysis and test the factor structure suggested in the exploratory analysis. Findings. The proposed factor structure for the items measuring ‘Uplifts’ proved to be a good fit to the data and the proposed factor structure for the items measuring ‘Hassles’ showed adequate fit. Conclusion. In nursing programmes adopting the academic model and combining university-based learning with placement experience, this instrument can be used to help identify the sources of stress or course demands that students rate as distressing and those that help them to achieve. The validity of the ISSN could be further evaluated in other education settings.