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831.
Computers have the potential to greatly increase the accuracy of judgments and decisions that are made in the area of psychological assessment. The validity of present-day computer programs are described in the first 2 articles of this Special Section. Both computer-based test interpretation programs and mechanical prediction rules (e.g., statistical prediction rules) are described. Limitations of present-day computer programs are described in the 3rd article along with methodological recommendations for building more powerful rules. In the 4th article, a statistical analysis (neural network modeling) is described that may allow us to build better rules. 相似文献
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Poon PN 《The Journal of medical humanities》2000,21(3):159-173
From carrots to frogs to sheep and finally to humans, the history of cloning is a fascinating study of the interplay between science and popular culture. Imagination and discovery provide mutual impetus in the evolving science and cultural phenomenon of cloning. Its history is a paradigm of science unfiction: What once belonged unequivocally on the pages of science fiction is now emerging in flesh and blood. Writers, movie producers, ethicists, and all manner of social commentators, no less than scientists, have all participated in the creation of the human clone as an idea and as a biological entity. While the clone stands apart as having only one genetic parent, it truly is a brainchild of multifarious origins. 相似文献
834.
A 7-subtest short form of the Wechsler Adult Intelligence Scale-III (WAIS-III) previously demonstrated good comparability in estimating Full Scale and Verbal IQ summary scores, with adequate comparability in estimating Performance IQ. In a mixed clinical sample of 295 patients, the current study assessed the equivalence of the index scores generated from the full and prorated WAIS-III. The results revealed correlations corrected for redundancy of .90, .86, .87, and .75 for the Verbal Comprehension (VCI), Perceptual Organization (POI), Working Memory (WMI), and Processing Speed (PSI) indexes, respectively. Although the 7-subtest short form of the WAIS-III was not designed to estimate index scores, adequate estimates are viable for VCI, POI, and WMI when the goal is to obtain group, rather than individual, data points. 相似文献
835.
Confirmatory factor analyses (CFAs) revealed 2 important characteristics of the standardization data of the Wechsler Adult Intelligence Scale Revised. One finding was that Digit Symbol fit better on an attentional factor in younger groups, but fit was better when Digit Symbol loaded on a visual-perceptual factor in older groups. A second observation was that specifying correlated errors or a fourth factor to explain covariance between Block Design and Object Assembly improved model fit in all age groups except 70- to 74-year-olds. The results illustrate the value of CFA and have implications for investigating other samples and other Wechsler tests. 相似文献
836.
Psychoneuroimmunology (PNI) is a rapidly evolving multidisciplinary field founded on the premise that psychosocial factors, the central nervous system, and the immune system are intimately linked. Following publication of scientific evidence supporting this link, a number of animal and human studies have been published, both inside and outside the area of human immunodeficiency virus (HIV) infection and acquired immunodeficiency syndrome. These studies support the existence of bidirectional feedback mechanisms operating between the brain and the immune system. To date, however, there is no all-encompassing model that predicts individual differences in the relationship among psychosocial factors, immunologic measures, and clinical disease progression in HIV type 1 (HIV-1) infection. This variability in human response has been explained by a number of cofactors (host as well as environmental) that appear to accelerate the course of the disease. Since psychosocial factors are highly amenable to behavioral interventions, several models for intervention research have been proposed to evaluate whether such interventions can enhance immune functioning, thereby curtailing disease progression. Examination of these interventions in the context of PNI and HIV-1 infection, however, is rather limited. Therefore, researchers and clinicians must not only consider conceptualizations and paradigms in this area of research, but also focus on empirically testable, theory-driven models that allow for the unique characteristics of individual patients. 相似文献
837.
An experiment on adaptive automation is described. Reliability of automated fault diagnosis, mode of fault management (manual vs. automated), and fault dynamics affect variables including root mean square error, avoidance of accidents and false shutdowns, subjective trust in the system, and operator self-confidence. Results are discussed in relation to levels of automation, models of trust and self-confidence, and theories of human-machine function allocation. Trust in automation but not self-confidence was strongly affected by automation reliability. Operators controlled a continuous process with difficulty only while performing fault management but could prevent unnecessary shutdowns. Final authority for decisions and action must be allocated to automation in time-critical situations. 相似文献
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Event-related brain potentials (ERPs) of 21 subjects were recorded in a choice reaction time task with a repeating eight-element long stimulus sequence. The regular event sequence was sometimes interrupted by 'perceptual' or by 'motor deviants' which both replaced an expected stimulus but either preserved or violated the sequence of motor responses. Response times confirmed that all subjects had acquired some knowledge of the sequential dependencies. By means of a post-experimental free recall and recognition test, subjects were classified as having either explicit or implicit knowledge of the event sequence. The ERPs showed different effects for different types of stimuli and the two groups. In the group of explicit learners, a larger N200 component was evoked by both types of deviants and a larger P300 by motor deviants only. In the group of implicit learners these 'perceptual components' remained unaffected. In contrast, in both groups of subjects the lateralized readiness potential (LRP) which accompanied motor deviants revealed a partial activation of the to be expected but incorrect response, i.e. motor learning. These results suggest that explicit learners acquire knowledge about both, stimulus and response dependencies while implicit learners acquire knowledge about response dependencies only. 相似文献