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81.
82.
Aslak Fyhri Torkel Bjørnskau Agathe Backer-Grøndahl 《Transportation Research Part F: Traffic Psychology and Behaviour》2012,15(5):612-624
Several studies have shown that bicycle helmets have the potential of reducing injuries from accidents. Yet, no studies have found good evidence of an injury reducing effect in countries that have introduced bicycle helmet legislation. Two of the most promising explanations for why helmet laws do not work as intended are risk compensation and shifts in the cycle population as a response to the law.The present article investigates whether the lack of effect of helmet wearing laws is due to risk compensation mechanisms or population shifts (i.e. discouraging cyclists with the lowest accident risk, and thereby increasing the overall average risk per cyclist). A random sample of 1504 bicycle owners in Norway responded to a questionnaire on among other things helmet use, bicycle equipment use, accident involvement, cycling behaviour and risk perception. Data were analysed by using structural equation model (SEM). The results show that the cyclist population in Norway can be divided into two sub-populations: one speed-happy group that cycle fast and have lots of cycle equipment including helmets, and one traditional kind of cyclist without much equipment, cycling slowly. With all the limitations that have to be placed on a cross sectional study such as this, the results indicate that at least part of the reason why helmet laws do not appear to be beneficial is that they disproportionately discourage the safest cyclists. 相似文献
83.
Two common strategies for successful foraging are learning to associate specific sensory cues with patches of prey ("associative learning") and using set decision-making rules to systematically scan for prey ("algorithmic search"). We investigated whether an animal's life history affects which of these two foraging strategies it is likely to use. Natterer's bats (Myotis nattereri) have slow life-history traits and we predicted they would be more likely to use associative learning. Common shrews (Sorex araneus) have fast life-history traits and we predicted that they would rely more heavily on routine-based search. Apart from their marked differences in life-history traits, these two mammals are similar in body size, brain weight, habitat, and diet. We assessed foraging strategy, associative learning ability, and retention time with a four-arm maze; one arm contained a food reward and was marked with four sensory stimuli. Bats and shrews differed significantly in their foraging strategies. Most bats learned to associate the sensory stimuli with the reward and remembered this association over time. Most shrews searched the maze using consistent decision-making rules, but did not learn or remember the association. We discuss these results in terms of life-history traits and other key differences between these species. Our results suggest a link between an animal's life-history strategy and its use of associative learning. 相似文献
84.
Friend influence over alcohol intoxication and delinquent behavior was examined as a function of relative peer acceptance in a 3-year study of Swedish youth (N = 184 girls, 145 boys). Participants were in the first year of secondary school (7th grade, M = 11.7 years old) or the first year of high school (10th grade, M = 15.3 years old) at the outset. Friends resembled one another before the friendship; resemblances were even greater after the friendship began. Resemblances continued to grow among those who remained friends one year later, but declined among those whose friendships dissolved. Partners were not equally responsible for increases in similarity. In stable friendships, the more accepted partner exerted greater influence over the less accepted partner, such that the greatest increases in problem behaviors were found among less accepted youth whose friends had higher initial levels of delinquency and alcohol intoxication. Unstable friends resembled random pairs of youth in that more- and less-accepted partners were comparably uninfluential. 相似文献
85.
The standard semantic definition of consequence with respect to a selected set X of symbols, in terms of truth preservation under replacement (Bolzano) or reinterpretation (Tarski) of symbols outside X, yields a function mapping X to a consequence relation \(\Rightarrow_X\). We investigate a function going in the other direction, thus extracting the constants of a given consequence relation, and we show that this function (a) retrieves the usual logical constants from the usual logical consequence relations, and (b) is an inverse to—more precisely, forms a Galois connection with—the Bolzano–Tarski function. 相似文献
86.
Exploring the associations between coping patterns for everyday stressors and mental health in young schoolchildren 总被引:1,自引:0,他引:1
The purposes of this study were to explore the structure of coping with everyday stressors in a young nonclinical population and examine the relationship between coping and mental health. A total of 1324 children from 91 second-grade classes in 35 schools participated. Mental health was assessed using the parent and teacher forms of the Strengths and Difficulties Questionnaire (Goodman, 1997), and coping was assessed by the Kidcope (Spirito et al., 1988) self-report checklist. Exploratory and confirmatory factor analyses suggested a three-factor structure of coping. Latent-variable regression analysis indicated that coping categories including both active and emotional strategies were associated with fewer mental health problems, whereas withdrawal and oppositional coping strategies were associated with greater mental health problems. With some important exceptions, the results replicated previous studies of adults and adolescents. The need for new, more comprehensive coping assessments is highlighted. 相似文献
87.
The present study focuses on how patients diagnosed with psychosis deal with a conflicting situation. In the study, two groups of patients were assessed. One group consisted of patients diagnosed with psychosis (n = 41), while the comparison group (n = 135) consisted of inpatients diagnosed either with anorexia nervosa or with bulimia nervosa. The groups were assessed using the Serial Color Word Test (S-CWT), designed for studying an individual's successive adaptation over time to a conflicting situation. The S-CWT differentiated the two groups regarding both reading time and adaptive styles. Patients diagnosed with psychosis had longer reading times and an adaptive style that was deviant throughout the test, indicating poorer cognitive functioning and more serious psychopathology. These problems may in turn influence functioning in work or study and daily living, all of which are important in treatment planning. 相似文献
88.
The Bergen Facebook Addiction Scale (BFAS), initially a pool of 18 items, three reflecting each of the six core elements of addiction (salience, mood modification, tolerance, withdrawal, conflict, and relapse), was constructed and administered to 423 students together with several other standardized self-report scales (Addictive Tendencies Scale, Online Sociability Scale, Facebook Attitude Scale, NEO-FFI, BIS/BAS scales, and Sleep questions). That item within each of the six addiction elements with the highest corrected item-total correlation was retained in the final scale. The factor structure of the scale was good (RMSEA = .046, CFI = .99) and coefficient alpha was .83. The 3-week test-retest reliability coefficient was .82. The scores converged with scores for other scales of Facebook activity. Also, they were positively related to Neuroticism and Extraversion, and negatively related to Conscientiousness. High scores on the new scale were associated with delayed bedtimes and rising times. 相似文献
89.
Andreassen CS Griffiths MD Hetland J Pallesen S 《Scandinavian journal of psychology》2012,53(3):265-272
Andreassen, C. S., Griffiths, M. D., Hetland, J. & Pallesen, S. (2012). Development of a work addiction scale. Scandinavian Journal of Psychology 53, 265–272. Research into excessive work has gained increasing attention over the last 20 years. Terms such as “workaholism,”“work addiction” and “excessive work” have been used interchangeably. Given the increase in empirical research, this study presents the development of the Bergen Work Addiction Scale (BWAS), a new psychometrically validated scale for the assessment of work addiction. A pool of 14 items, with two reflecting each of seven core elements of addiction (i.e., salience, mood modification, tolerance, withdrawal, conflict, relapse, and problems) was initially constructed. The items were then administered to two samples, one recruited by a web survey following a television broadcast about workaholism (n = 11,769) and one comprising participants in the second wave of a longitudinal internet‐based survey about working life (n = 368). The items with the highest corrected item‐total correlation from within each of the seven addiction elements were retained in the final scale. The assumed one‐factor solution of the refined seven‐item scale was acceptable (root mean square error of approximation = 0.077, Comparative Fit Index = 0.96, Tucker‐Lewis Index = 0.95) and the internal reliability of the two samples were 0.84 and 0.80, respectively. The scores of the BWAS converged with scores on other workaholism scales, except for a Work Enjoyment subscale. A suggested cut‐off for categorization of workaholics showed good discriminative ability in terms of working hours, leadership position, and subjective health complaints. It is concluded that the BWAS has good psychometric properties. 相似文献
90.
Adolescent smoking behavior is assumed to be associated with smoking outcome expectancies. Results in this paper are based on data from the control group of two data collections among Norwegian secondary school students taken approximately 30 months apart (T1 and T2). The dimensionality of smoking outcome expectancies was the same at both time points, revealing three components ("Addicted", "Not harmful" and "Social"). After correction for attenuation, the Pearson's correlation between T1 and T2 was 0.41 for the total sumscore, indicating low to moderate relative stability. When examining smoking expectancy sumscore means by smoking habits at T1 and T2, never smokers were different from smokers on both occasions. Never smokers scored low on "Social" and "Not harmful", and high on "Addictive". All associations were statistically significant (p < 0.001). The "Social" dimension was the strongest predictor of smoking behavior at T1 and T2. One of the outcome expectancy sumscores ("Addictive") at T1 predicted smoking habits at T2 after controlling for smoking habits at T1 (p < 0.01). This predictor was significant also after entering outcome expectancy sumscores at T2 into the model (p < 0.05). These results indicate that outcome expectations other than the health-related ones should be paid attention to when planning new prevention programs. 相似文献