994 resultados para cognitive appraisal
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This paper discusses users’ query reformulation behaviour while searching information on the Web. Query reformulations have emerged as an important component of Web search behaviour and human-computer interaction (HCI) because a user’s success of information retrieval (IR) depends on how he or she formulates queries. There are various factors, such as cognitive styles, that influence users’ query reformulation behaviour. Understanding how users with different cognitive styles formulate their queries while performing Web searches can help HCI researchers and information systems (IS) developers to provide assistance to the users. This paper aims to examine the effects of users’ cognitive styles on their query reformation behaviour. To achieve the goal of the study, a user study was conducted in which a total of 3613 search terms and 872 search queries were submitted by 50 users who engaged in 150 scenario-based search tasks. Riding’s (1991) Cognitive Style Analysis (CSA) test was used to assess users’ cognitive style as wholist or analytic, and verbaliser or imager. The study findings show that users’ query reformulation behaviour is affected by their cognitive styles. The results reveal that analytic users tended to prefer Add queries while all other users preferred New queries. A significant difference was found among wholists and analytics in the manner they performed Remove query reformulations. Future HCI researchers and IS developers can utilize the study results to develop interactive and user-cantered search model, and to provide context-based query suggestions for users.
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Spatial navigation requires the processing of complex, disparate and often ambiguous sensory data. The neurocomputations underpinning this vital ability remain poorly understood. Controversy remains as to whether multimodal sensory information must be combined into a unified representation, consistent with Tolman's "cognitive map", or whether differential activation of independent navigation modules suffice to explain observed navigation behaviour. Here we demonstrate that key neural correlates of spatial navigation in darkness cannot be explained if the path integration system acted independently of boundary (landmark) information. In vivo recordings demonstrate that the rodent head direction (HD) system becomes unstable within three minutes without vision. In contrast, rodents maintain stable place fields and grid fields for over half an hour without vision. Using a simple HD error model, we show analytically that idiothetic path integration (iPI) alone cannot be used to maintain any stable place representation beyond two to three minutes. We then use a measure of place stability based on information theoretic principles to prove that featureless boundaries alone cannot be used to improve localization above chance level. Having shown that neither iPI nor boundaries alone are sufficient, we then address the question of whether their combination is sufficient and - we conjecture - necessary to maintain place stability for prolonged periods without vision. We addressed this question in simulations and robot experiments using a navigation model comprising of a particle filter and boundary map. The model replicates published experimental results on place field and grid field stability without vision, and makes testable predictions including place field splitting and grid field rescaling if the true arena geometry differs from the acquired boundary map. We discuss our findings in light of current theories of animal navigation and neuronal computation, and elaborate on their implications and significance for the design, analysis and interpretation of experiments.
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Adolescent risk-taking behavior has potentially serious injury consequences and school-based behavior change programs provide potential for reducing such harm. A well-designed program is likely to be theory-based and ecologically valid however it is rare that the operationalisation process of theories is described. The aim of this paper is to outline how the Theory of Planned Behavior and Cognitive Behavioral Therapy informed intervention design in a school setting. Teacher interviews provided insights into strategies that might be implemented within the curriculum and provided detail used to operationalise theory constructs. Benefits and challenges in applying both theories are described with examples from an injury prevention program, Skills for Preventing Injury in Youth.
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Objective The main aim of the present study was to identify food consumption in Sri Lankan adults based on serving characteristics. Design Cross-sectional study. Fruits, vegetables, starch, meat, pulses, dairy products and added sugars in the diet were assessed with portion sizes estimated using standard methods. Setting Twelve randomly selected clusters from the Sri Lanka Diabetes and Cardiovascular Study. Subjects Six hundred non-institutionalized adults. Results The daily intake of fruit (0·43), vegetable (1·73) and dairy (0·39) portions were well below national recommendations. Only 3·5 % of adults consumed the recommended 5 portions of fruits and vegetables/d; over a third of the population consumed no dairy products and fewer than 1 % of adults consumed 2 portions/d. In contrast, Sri Lankan adults consumed over 14 portions of starch and 3·5 portions of added sugars daily. Almost 70 % of those studied exceeded the upper limit of the recommendations for starch intake. The total daily number of meat and pulse portions was 2·78. Conclusions Dietary guidelines emphasize the importance of a balanced and varied diet; however, a substantial proportion of the Sri Lankan population studied failed to achieve such a recommendation. Nutrition-related diseases in the country may be closely correlated with unhealthy eating habits.
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Cognitive radio is an emerging technology proposing the concept of dynamic spec- trum access as a solution to the looming problem of spectrum scarcity caused by the growth in wireless communication systems. Under the proposed concept, non- licensed, secondary users (SU) can access spectrum owned by licensed, primary users (PU) so long as interference to PU are kept minimal. Spectrum sensing is a crucial task in cognitive radio whereby the SU senses the spectrum to detect the presence or absence of any PU signal. Conventional spectrum sensing assumes the PU signal as ‘stationary’ and remains in the same activity state during the sensing cycle, while an emerging trend models PU as ‘non-stationary’ and undergoes state changes. Existing studies have focused on non-stationary PU during the transmission period, however very little research considered the impact on spectrum sensing when the PU is non-stationary during the sensing period. The concept of PU duty cycle is developed as a tool to analyse the performance of spectrum sensing detectors when detecting non-stationary PU signals. New detectors are also proposed to optimise detection with respect to duty cycle ex- hibited by the PU. This research consists of two major investigations. The first stage investigates the impact of duty cycle on the performance of existing detec- tors and the extent of the problem in existing studies. The second stage develops new detection models and frameworks to ensure the integrity of spectrum sensing when detecting non-stationary PU signals. The first investigation demonstrates that conventional signal model formulated for stationary PU does not accurately reflect the behaviour of a non-stationary PU. Therefore the performance calculated and assumed to be achievable by the conventional detector does not reflect actual performance achieved. Through analysing the statistical properties of duty cycle, performance degradation is proved to be a problem that cannot be easily neglected in existing sensing studies when PU is modelled as non-stationary. The second investigation presents detectors that are aware of the duty cycle ex- hibited by a non-stationary PU. A two stage detection model is proposed to improve the detection performance and robustness to changes in duty cycle. This detector is most suitable for applications that require long sensing periods. A second detector, the duty cycle based energy detector is formulated by integrat- ing the distribution of duty cycle into the test statistic of the energy detector and suitable for short sensing periods. The decision threshold is optimised with respect to the traffic model of the PU, hence the proposed detector can calculate average detection performance that reflect realistic results. A detection framework for the application of spectrum sensing optimisation is proposed to provide clear guidance on the constraints on sensing and detection model. Following this framework will ensure the signal model accurately reflects practical behaviour while the detection model implemented is also suitable for the desired detection assumption. Based on this framework, a spectrum sensing optimisation algorithm is further developed to maximise the sensing efficiency for non-stationary PU. New optimisation constraints are derived to account for any PU state changes within the sensing cycle while implementing the proposed duty cycle based detector.
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This article critically analyses the role that criminological theory and specific policy formulations of culture play in the New Zealand state’s response to the over-representation of Māori in the criminal justice system. Part one provides an overview of the changing criminological explanations of, and responses to, Māori offending in New Zealand from the 1980s onwards and how these understandings extended colonialist approaches to Māori and crime into the neo-colonial context. In particular, we chart the shift in policy development from theorising Māori offending as attributable to loss of cultural identity to a focus on socio-economic and institutional antecedents and, finally, through the risk factors, assessment, and criminogenic needs approaches that have gained prominence in the current policy context. In part two, the focus moves to the strategies employed by members of the academy to elevate their own epistemological constructions of Māori social reality within the policy development process. In particular, the critique scrutinises recent attempts to portray Indigenous responses to social harm as “unscientific” and, in part, responsible for the continuing over-representation of Māori in New Zealand’s criminal justice system. The purpose of this analysis is to focus the critical, criminological gaze firmly on the activities of policy makers and administrative criminologists, to examine how their policies and approaches impact on Māori as an Indigenous people.
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This paper describes a process undertaken to develop and review five clinical vignettes to be used in geriatric nursing educational research. The purpose of this process was to provide valid depictions of delirium and its subtypes and distinguish delirium from dementia. Five vignettes depicting hospital bedside interactions between nursing staff, family, and an older patient who displayed signs of one of the following conditions: delirium (hyper and hypo-active types respectively), dementia, or delirium (both types) superimposed on dementia were constructed. Vignette accuracy and reliability was established using a multistage process that culminated in formal review by a group of ten international nursing and medical delirium experts. The final five vignettes accurately depicted the given scenario as agreed by the experts and were at an appropriate level of simplicity and clarity. Given the increased interest in vignettes for both nursing research and educational purposes, the described method of vignette development and review has the ability to assist other vignette developers in creating reliable representations of their desired clinical scenarios.
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Background: The high rates of comorbid depression and substance use in young people have been associated with a range of adverse outcomes. Yet, few treatment studies have been conducted with this population. Objective: To determine if the addition of Motivational Interviewing and Cognitive Behaviour Therapy (MI/CBT) to standard alcohol and other drug (AOD) care improves the outcomes of young people with comorbid depression and substance use. Participants and Setting: Participants comprised 88 young people with comorbid depression (Kessler 10 score of > 17) and substance use (mainly alcohol/cannabis) seeking treatment at two youth AOD services in Melbourne, Australia. Sixty young people received MI/CBT in addition to standard care (SC) and 28 received SC alone. Outcomes Measures: Primary outcome measures were depressive symptoms and drug and alcohol use in the past month. Assessments were conducted at baseline, 3 and 6 months follow up. Results and Conclusions: The addition of MI/CBT to SC was associated with a significantly greater rate of change in depression, cannabis use, motivation to change substance use and social contact in the first 3 months. However, those who received SC had achieved similar improvements on these variables by 6 months follow up. All young people achieved significant improvements in functioning and quality of life variables over time, regardless of the treatment group. No changes in alcohol or other drug use were found in either group. The delivery of MI/CBT in addition to standard AOD care may offer accelerated treatment gains in the short-term.
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Objective To explore whether improvements in physical activity following the MobileMums intervention were mediated by changes in Social Cognitive Theory (SCT) constructs targeted in the intervention (barrier self efficacy, goal setting skills, outcome expectancy, social support, and perceived environmental opportunity for exercise). This paper also examined if the mediating constructs differed between initial (baseline to 6 weeks) and overall (baseline to 13 weeks) changes in physical activity. Methods Secondary analysis of data from a randomized controlled trial involving 88 postnatal women (<12 months postpartum). Participants were randomized to receive either the 12-week MobileMums intervention or a minimal-contact control condition. Physical activity and proposed mediators were assessed by self-report at baseline, 6 weeks, and 13 weeks. Walking for Exercise frequency was assessed using the Australian Women's Activity Survey and frequency of moderate-to-vigorous physical activity (MVPA) was assessed using a single-item question. Results Initial improvements in goal-setting skills mediated the relationship between experimental condition and initial changes in MVPA, αβ (95% CI) = 0.23(0.01, 0.59), and Walking for Exercise, αβ (95% CI) = 0.34(0.06, 0.73). Initial improvements in barrier self efficacy mediated the relationship between experimental condition and initial change in MVPA, αβ (95% CI) = 0.36(0.12, 0.65), but not Walking for Exercise. None of the SCT outcomes significantly mediated the relationship between experimental condition and overall (baseline to 13 weeks) change in frequency of MVPA or Walking for Exercise. Conclusion Future interventions with postnatal women using SCT should target barrier self-efficacy and goal setting skills in order to increase physical activity. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
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The aim of this study was to examine older adults’ understanding and interpretation of a validated questionnaire for physical activity surveillance, the Active Australia Survey (AAS). To address this aim, cognitive interviewing techniques were used during face-to-face semi-structured interviews with 44 adults aged 65-89 years. Qualitative data analysis revealed that participants were confused with questionnaire phrasing, misunderstood the scope of activities to include in answers, and misunderstood the time frame of activities to report. They also struggled to accurately estimate the frequency and duration of their activities. Our findings suggest that AAS questions may be interpreted differently by older adults than intended by survey developers. Findings also suggest that older adults use a range of methods for calculating PA frequency and duration. The issues revealed in this study may be useful for adapting AAS for use in older community-dwelling adults.
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Sensory imagery is a powerful tool for inducing craving because it is a key component of the cognitive system that underpins human motivation. The role of sensory imagery in motivation is explained by Elaborated Intrusion (EI) theory. Imagery plays an important role in motivation because it conveys the emotional qualities of the desired event, mimicking anticipated pleasure or relief, and continual elaboration of the imagery ensures that the target stays in mind. We argue that craving is a conscious state, intervening between unconscious triggers and consumption, and summarise evidence that interfering with sensory imagery can weaken cravings. We argue that treatments for addiction can be enhanced by the application of EI theory to maintain motivation, and assist in the management of craving in high-risk situations.
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A clear understanding of the cognitive-emotional processes underpinning desires to overconsume foods and adopt sedentary lifestyles can inform the development of more effective interventions to promote healthy eating and physical activity. The Elaborated Intrusion Theory of Desires offers a framework that can help in this endeavor through its emphases on the roles of intrusive thoughts and elaboration of multisensory imagery. There is now substantial evidence that tasks that compete for limited working memory resources with food-related imagery can reduce desires to eat that food, and that positive imagery can promote functional behavior. Meditation mindfulness can also short-circuit elaboration of dysfunctional cognition. Functional Decision Making is an approach that applies laboratory-based research on desire, to provide a motivational intervention to establish and entrench behavior changes, so healthy eating and physical activity become everyday habits.
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Self-efficacy has two cognitive components, efficacy expectations and outcome expectations, and their influence on behavior change is synergistic. Efficacy expectation is effected by four main sources of information provided by direct and indirect experiences. The four sources of information are performance accomplishments, vicarious experience, verbal persuasion and self-appraisal. How to measure and develop interventions is an important issue at present. This article clearly analyzes the relationship between variables of the self-efficacy model and explains the implementation of self-efficacy enhancing interventions and instruments in order to test the model. Through the process of the use of theory and feasibility in clinical practice, it is expected that professional medical care personnel should firstly familiarize themselves with the self-efficiency model and concept, and then flexibly promote it in professional fields clinical practice, chronic disease care and health promotion.
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Recent research has proposed Neo-Piagetian theory as a useful way of describing the cognitive development of novice programmers. Neo-Piagetian theory may also be a useful way to classify materials used in learning and assessment. If Neo-Piagetian coding of learning resources is to be useful then it is important that practitioners can learn it and apply it reliably. We describe the design of an interactive web-based tutorial for Neo-Piagetian categorization of assessment tasks. We also report an evaluation of the tutorial's effectiveness, in which twenty computer science educators participated. The average classification accuracy of the participants on each of the three Neo-Piagetian stages were 85%, 71% and 78%. Participants also rated their agreement with the expert classifications, and indicated high agreement (91%, 83% and 91% across the three Neo-Piagetian stages). Self-rated confidence in applying Neo-Piagetian theory to classifying programming questions before and after the tutorial were 29% and 75% respectively. Our key contribution is the demonstration of the feasibility of the Neo-Piagetian approach to classifying assessment materials, by demonstrating that it is learnable and can be applied reliably by a group of educators. Our tutorial is freely available as a community resource.