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941.
A laboratory experiment by U.S. public health researchers Hall et al. claimed to demonstrate that a graphic picture-and-text warning label placed on so-called sugary drinks would substantially reduce parents' purchase of them for their children. Hall et al., however, misclassified the alleged “sugary drinks,” omitting those containing natural but equally harmful sugars such as fructose in fruit juice and lactose in milk. They also implied that artificially sweetened “non-sugary” drinks are harmless when available research indicates otherwise. The experiment was further invalidated by the fact that warning labels are illegal in the U.S., and those that Hall et al. used would not be permitted in any case because they partially obscured the manufacturer's brand label. There were many other methodological problems with Hall et al.'s experiment, among them the failure to do what any competent consumer researcher would do—namely ask the parents afterwards why they made the choices that they did.  相似文献   
942.
In a recent article published in this journal, Yuan and Fang (British Journal of Mathematical and Statistical Psychology, 2023) suggest comparing structural equation modeling (SEM), also known as covariance-based SEM (CB-SEM), estimated by normal-distribution-based maximum likelihood (NML), to regression analysis with (weighted) composites estimated by least squares (LS) in terms of their signal-to-noise ratio (SNR). They summarize their findings in the statement that “[c]ontrary to the common belief that CB-SEM is the preferred method for the analysis of observational data, this article shows that regression analysis via weighted composites yields parameter estimates with much smaller standard errors, and thus corresponds to greater values of the [SNR].” In our commentary, we show that Yuan and Fang have made several incorrect assumptions and claims. Consequently, we recommend that empirical researchers not base their methodological choice regarding CB-SEM and regression analysis with composites on the findings of Yuan and Fang as these findings are premature and require further research.  相似文献   
943.
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945.
Categorical moderators are often included in mixed-effects meta-analysis to explain heterogeneity in effect sizes. An assumption in tests of categorical moderator effects is that of a constant between-study variance across all levels of the moderator. Although it rarely receives serious thought, there can be statistical ramifications to upholding this assumption. We propose that researchers should instead default to assuming unequal between-study variances when analysing categorical moderators. To achieve this, we suggest using a mixed-effects location-scale model (MELSM) to allow group-specific estimates for the between-study variance. In two extensive simulation studies, we show that in terms of Type I error and statistical power, little is lost by using the MELSM for moderator tests, but there can be serious costs when an equal variance mixed-effects model (MEM) is used. Most notably, in scenarios with balanced sample sizes or equal between-study variance, the Type I error and power rates are nearly identical between the MEM and the MELSM. On the other hand, with imbalanced sample sizes and unequal variances, the Type I error rate under the MEM can be grossly inflated or overly conservative, whereas the MELSM does comparatively well in controlling the Type I error across the majority of cases. A notable exception where the MELSM did not clearly outperform the MEM was in the case of few studies (e.g., 5). With respect to power, the MELSM had similar or higher power than the MEM in conditions where the latter produced non-inflated Type 1 error rates. Together, our results support the idea that assuming unequal between-study variances is preferred as a default strategy when testing categorical moderators.  相似文献   
946.
Facial examiners make visual comparisons of face images to establish the identities of persons in police investigations. This study utilised eye-tracking and an individual differences approach to investigate whether these experts exhibit specialist viewing behaviours during identification, by comparing facial examiners with forensic fingerprint analysts and untrained novices across three tasks. These comprised of face matching under unlimited (Experiment 1) and time-restricted viewing (Experiment 2), and with a feature-comparison protocol derived from examiner casework procedures (Experiment 3). Facial examiners exhibited individual differences in facial comparison accuracy and did not consistently outperform fingerprint analysts and novices. Their behaviour was also marked by similarities to the comparison groups in terms of how faces were viewed, as evidenced from eye movements, and how faces were perceived, based on the made feature judgements and identification decisions. These findings further understanding of how facial comparisons are performed and clarify the nature of examiner expertise.  相似文献   
947.
948.
The objective of the present study was to examine if the Outcome Bias also occurs in pilots flying under instrument flight rules (IFR). In a scenario-based survey, 60 pilots evaluated weather-related decisions made by hypothetical pilots. Participants rated the decisions as better, less risky, and regarded the probability that they would have made the same decision as higher when they were followed by a positive outcome, than when they were followed by a negative outcome. This effect showed likewise for novice pilots and for experienced pilots. These findings could be relevant for the flight-related decision-making of pilots, which sometimes is affected by the decisions made by third-party pilots. In particular, decisions made by other pilots that have led to positive outcomes might be hastily followed, whereas those that have led to negative outcomes might be hastily rejected.  相似文献   
949.
The COVID-19 pandemic has highlighted the need for further research evaluating the validity of conducting a battery of neuropsychological assessments virtually compared with face-to-face administration. Previous research has suggested that some neuropsychological assessments yield valid results when administered virtually, however, much of the previous research focused on older adults. To determine the validity of virtually administered neuropsychological tests, 28 healthy participants were assessed using a within-subjects, counter-balanced design. Participants completed a neuropsychological assessment battery covering tests of general intellectual functioning, memory and attention, executive functioning, language and information processing speed, as well as effort. There was no significant difference between face-to-face administration of the neuropsychological battery compared with virtual administration for the majority of the tests used. However, there were significant differences in the Colour Naming Task, with participants making fewer errors on the colour naming task and inhibition/switching task when administered virtually compared with face-to-face administration. There was also a significant age cohort effect in the inhibition/switching task. There was also a trending significant difference in mode of administration for the Verbal Fluency Task. Virtually administered neuropsychological assessments largely provide a valid alternative to face-to-face assessments; however, consideration must be given to test selection as well as the population of participants that are being assessed. Other important considerations must focus on preserving the security and integrity of test materials, as well as administration in a medico-legal setting. Future research should focus on validating assessments with specific patient populations and developing a neuropsychological assessment battery using information technology.  相似文献   
950.
Previous studies of autobiographical memory (AM) in schizophrenia yielded a reduction of specificity, richness of details and conscious recollection, which indicate both, quantitative and qualitative AM changes. However, their associations with psychopathological symptoms and neuropsychological deficits were not resolved. Therefore, we sought to investigate AM with respect to psychopathology and neuropsychology in patients with chronic schizophrenia to rule out the influence of different courses of the disease. AM of four lifetime periods was examined in 75 patients and 50 healthy controls by using a semi-structured interview. The recalled episodes were rated for memory specificity. Subsequently, one single event of each period of life was rated for details and experiential aspects of reliving (originality, vividness/visual imagery, emotional re-experiencing and emotional valence). When contrasted with healthy controls, patients recalled a significantly reduced number of episodes and personal semantic facts; moreover, memory specificity of AM was significantly lower in patients than controls. While the richness of details calculated for single events showed only minor, non-significant group differences, vividness and emotional re-experiencing were significantly less pronounced in the patient group. Along with this, AM performance correlated significantly with negative symptoms including apathy as well as verbal memory and executive functions. Our results underline the significance of overgenerality as a key feature of AM in schizophrenia as well as a dissociation between intact number of details of single events and reduced vividness and emotional re-experiencing. The extent of negative symptoms including apathy and impairments of verbal memory/executive functions may explain AM deficits in chronic schizophrenia.  相似文献   
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