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791.
Karl Halvor Teigen 《Thinking & reasoning》2013,19(2):147-177
Occasionally, people are called upon to estimate probabilities after an event has occurred. In hindsight, was this an outcome we could have expected? Could things easily have turned out differently? One strategy for performing post hoc probability judgements would be to mentally turn the clock back and reconstruct one's expectations before the event. But if asked about the probability of an alternative, counterfactual outcome, a simpler strategy is available, based on this outcome's perceived closeness to what actually happened. The article presents five studies exploring the relationship between counterfactual closeness and counterfactual probability. The first study indicates that post hoc probabilities typically refer to the counterfactual rather than the factual outcome. Studies 2-5 show that physical, temporal, or conceptual proximity play a decisive role for post hoc probability assessments of counterfactual events. When margins are narrow, the probabilities of, for instance, winning a match (when losing), and of losing (when actually winning) may even be rated higher than the corresponding probabilities of what really happened. Closeness is also more often referred to, and rated to be a better reason for believing there is a “good chance” of the counterfactual rather than of the factual result occurring. Finally, the closeness of the alternative outcome in success and failure stories is shown to be significantly correlated to its rated probability. 相似文献
792.
Nearly all framing studies to date presuppose unbiased estimates. If an expert says that “programme A will save 200 people”, it is tacitly assumed that this prediction is correct. In real life this is rarely the case. In the present study people were asked to evaluate such claims that eventually turned out to be incorrect. Participants in five experiments were asked to rate how correct, and how true, are predictions and reports that either overstate or understate the facts. Overall, understatements were considered more accurate than overstatements, and pessimistic statements were better than overly optimistic ones. Thus predictions of an outcome that turns out better than expected should preferably have been presented in a positive frame (e.g., money saved), whereas outcomes that turn out worse than expected will appear less “wrong” if predictions were presented in a negative frame (e.g., money lost). Parallel studies were performed with wrong predictions and incorrect factual claims (lies). In all studies, correctness ratings were affected by the way the statements were framed. 相似文献
793.
Karl Peltzer 《Journal of Psychology in Africa》2013,23(3):365-370
Using the data from the South African World Health Survey (WHS), the current study aims to assess the self-reported prevalence of diabetes and associated risk factors by socio-economic characteristics in South Africa. A population-based survey of 2314 participants (1116 men and 1236 women) was conducted in South Africa in 2003. Results indicate an overall self-reported diabetes prevalence of 9.1%, 7.1% for men and 10.8% for women. In terms of diabetes risk factors, high rates of overweight or obesity (58.4%), physical inactivity (55.2%), less than 5 servings of fruits and vegetables in a day (69.3%), and medium or high stress levels (63.3%) were found; 18.4% were smoking daily and 7.3% were risky drinkers. Univariate regression analyses found that from the six different risk factors none apart from having high stress were associated with the occurrence of diabetes. Greater age was associated with obesity and inversely associated with insufficient consumption of fruits and vegetables. Daily smoking and being physically inactive were inversely associated with risky drinking. Low socioeconomic background was associated with unhealthy diet, physical inactivity and stress. 相似文献
794.
The aim of this study was to investigate the association between post-traumatic stress disorder (PTSD) and health risk behaviours among persons 15 years and older in South Africa. We analysed data from the South African National Health and Nutrition Examination Survey (SANHANES-1, 2012) (N = 15 201; mean age = 36.9 years, SD = 16.5; 2.1% with PSTD, 4.0% with partial PTSD). The survey included questions from validated measures of the following health risk behaviours: problem drinking, current tobacco use, physical activity, sedentary behaviour, vegetable consumption, and fast food and frequent soft drinks consumption. In adjusted logistic regression analysis, only self-reporting with PTSD was associated with problem drinking. The data did not yield significant association between PTSD status and any of the other health risk behaviours (tobacco use, low physical activity, and fast food consumption). 相似文献
795.
The aim of this study was to determine mental health correlates of HIV risk behaviour and self-reported STIs/HIV infection among university students in 22 low, middle and high income countries. Data on mental health and HIV risk were collected from 16 567 undergraduate university students (mean age 20.9, SD = 2.9) from 23 universities in 22 countries across Asia, Africa and the Americas. Results indicate that overall 16.8% of the students had two or more sexual partners in the past 12 months, and among the sexually active, 73.7% had inconsistently used a condom in the past three months with their primary sexual partner, 3.2% had ever been diagnosed with a sexually transmitted infection (STI) and 0.6% had been diagnosed with HIV. In multivariate logistic regression poorer mental health and child abuse (physical and sexual) were associated with HIV risk behaviour, and child abuse (physical and sexual) was associated with STI and HIV positive diagnoses. 相似文献
796.
The aim of this study was to assess the prevalence and associated factors of problem drinking among South African youth (18–24 years). A cross-sectional population-based household survey was conducted using a multi-stage stratified cluster sampling approach. The total sample included 3123 participants (age range 18–24 years, 45.4% women) from four of nine provinces in South Africa. Results indicate that current alcohol was relatively more common among male (40.7%) than female youths (21.3%). Similarly, hazardous or harmful drinking was more prevalent among males (24.3%) than among women (12.9%). In multivariable analyses among men and women high on sexually permissiveness had hazardous or harmful alcohol use. Lifestyle including high peer pressure, and spending more nights away in a week were associated with hazardous or harmful alcohol use. 相似文献
797.
Karl Peltzer 《Journal of Psychology in Africa》2013,23(4):401-404
The study aimed to investigate the relationship between sedentary behaviour and sleep problems in a large national community sample in South Africa. We analysed an existing cross-sectional population data set, the “South African National Health and Nutrition Examination Survey”. The sample included 13 555 individuals (median age 34.0 years, interquartile range 25, range 15–98 years). Overall, the study population engaged < 4 hours (49.5%), 4 – < 8 hours (37.2%), 8 – < 11 hours (9.7%), and 11 or more hours (3.6%) in sedentary time a day. The prevalence of sleeping problems was 6.4% and 6.7% in the less than 4 and less than 8 hours sedentary time categories, respectively. The prevalence of sleeping problems was 9.8% and 9.4% in the less than 11 hours and 11 or more hours sedentary time categories, respectively. In the final adjusted logistic regression model, among 50 years and older, the highest sedentary time category was associated with sleep problems, while there was no association in the younger (15–49 years) age group and in the overall model. This could mean that persons at older age with sedentary behaviour are at an increased risk of sleep problems. 相似文献
798.
Karl Peltzer Nancy Phaswana-Mafuya George Petros 《Journal of Psychology in Africa》2013,23(2):247-251
The study assessed the prevalence of hazardous alcohol use among people living with HIV (PLHIV) and its correlates with socio-economic characteristics, disease variables and ART adherence in South Africa. The sample included 607 PLHIV (males =475, females =132; age range =18–61), sampled by all districts in the Eastern Cape. Participants were recruited through a health facility in the community through key informants or a support group. Results indicate that male PLHIV were more often than female PLHIV “past month” (18.9% vs. 6.1%) and hazardous alcohol drinkers (6.1% vs. 2.7%); using a cut-off score of 8 and more on the Alcohol Use Disorders Identification Test (AUDIT). Not having a disability grant for HIV/AIDS and the disability grant terminated were both related to past month alcohol use, while having the “disability grant stopped” was also related with hazardous or harmful drinking. Not having an AIDS diagnosis and not being on ART were both associated with past month alcohol use and hazardous or harmful drinking. CD4 counts and non-adherence to ART were both not significantly related with alcohol use status. Brief health provider initiated alcohol interventions for PLHIV should be promoted, with emphasis on targeting men. 相似文献
799.
800.
Christiane B. Wiebel Matteo Valsecchi Karl R. Gegenfurtner 《Attention, perception & psychophysics》2013,75(5):954-966
We studied the time course of material categorization in natural images relative to superordinate and basic-level object categorization, using a backward-masking paradigm. We manipulated several low-level features of the images—including luminance, contrast, and color—to assess their potential contributions. The results showed that the speed of material categorization was roughly comparable to the speed of basic-level object categorization, but slower than that of superordinate object categorization. The performance seemed to be crucially mediated by low-level factors, with color leading to a solid increase in performance for material categorization. At longer presentation durations, material categorization was less accurate than both types of object categorization. Taken together, our results show that material categorization can be as fast as basic-level object categorization, but is less accurate. 相似文献