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191.
鉴于人体研究的局限性,动物模型在哮喘研究中起了无可替代的作用。尤其在阐明哮喘的病理生理和免疫学机制方面,动物研究可以给我们提供人体研究难以得到的结果。但是,由于人类与动物之间存在的差别,动物模型的研究结果应用于人类时还需要进一步评估。本文将对哮喘动物模型在哮喘研究中的作用及其局限性作一介绍。  相似文献   
192.
While clergy are recognized by their faith communities as important sources of mental health care, questions persist as to the treatment strategies they employ and endorse. This has implication for their likelihood to encourage their members to utilize professional mental health care resources. In this study, a modified version of the treatment portion of the Opinions about Psychological Problems (OPP, Barker, Pistrang & Shapiro, 1983) is used to examine the treatment strategies endorsed by a representative sample of Singaporean clergymen. Besides attempting to show the usefulness of this modified scale, this study highlights that clergy endorse psychological models the most when these models are congruent to their theological belief system. Organic and popular Charismatic deliverance treatment models received less support. Mathew Mathews recently submitted his Ph.D. thesis entitled Clergy & Counsellors: Mental health care in Singapore. He is actively researching issues at the intersection of religion and health including the role of religion in help seeking intentions.  相似文献   
193.
A component-functions model of choice behavior is proposed for performance on interdependent concurrent variable-interval (VI) variable-interval schedules based on the product of two component functions, one that enhances behavior and one that reduces behavior. The model is the solution to the symmetrical pair of differential equations describing behavioral changes with respect to two categories of reinforcers: enhancing and reducing, or excitatory and inhibitory. The model describes residence time in interdependent concurrent VI VI schedules constructed from arithmetic and exponential distributions. The model describes the data reported by Alsop and Elliffe (1988) and Elliffe and Alsop (1996) with a variance accounted for of 87% compared to 64% accounted for by the Davison and Hunter (1976) model and 42% by Herrnstein's (1970) hyperbola. The model can explain matching, undermatching, and overmatching in the same subject under different procedures and has the potential to be extended to performance on concurrent schedules with more than two alternatives, multiple schedules, and single schedules. Thus, it can be considered as an alternative to Herrnstein's quantitative law of effect.  相似文献   
194.
Almost all admit that there is beauty in the natural world. Many suspect that such beauty is more than an adornment of nature. Few in our contemporary world suggest that this beauty is an empirical principle of the natural world itself and instead relegate beauty to the eye and mind of the beholder. Guided by theological and scientific insight, the authors propose that such exclusion is no longer tenable, at least in the data of modern biology and in our view of the natural world in general. More important, we believe an empirical aesthetics exists that can help guide experimental design and development of computational models in biology. Moreover, because theology and science can both contribute toward and equally profit from such an aesthetics, we propose that this empirical aesthetics provides the foundation for a living synergy between theology and science.  相似文献   
195.
Using a series of laboratory markets, this paper provides evidence that a willingness to engage in speculative trade is largely driven by a failure of traders to account for information about value implicit in other traders’ actions and that this behavior arises because traders construct myopic mental models that ignore the perspective of other traders. In a baseline set of markets, where traders are prompted to estimate fundamental value but are not overtly prompted to consider disagreement, I find that traders are generally insensitive to adverse selection and readily engage in suboptimal, speculative trade. Moreover, this effect does not decline across trials suggesting that market feedback alone is unlikely to correct traders’ behavior. In contrast, when traders are prompted to assess disagreement over asset values or when they trade in more transparent markets, they appear less willing to “agree to disagree.” These results provide insight into why investors depart from rational trading strategies and how investor psychology will influence trading behavior.  相似文献   
196.
The present study examined how the effects of three audiotapes containing different types of social comparison information on the mood of cancer patients depended on the level of neuroticism. On the procedural tape, a man and woman discussed the process of radiation therapy, on the emotion tape, they focussed on emotional reactions to their illness and treatment, while on the coping tape they focussed on the way they had been coping. A validation study among 115 students showed that the tapes were perceived as they were intended. The main study was conducted among 226 patients who were about to undergo radiation therapy. Compared to patients in the control group, as patients were higher in neuroticism, they reported less negative mood after listening to the procedural and the coping tape. Furthermore, as patients were higher in neuroticism, they reported less negative mood after listening to the coping tape than to the emotion tape. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
197.
Two experiments explored the mapping between language and mental representations of visual scenes. In both experiments, participants viewed, for example, a scene depicting a woman, a wine glass and bottle on the floor, an empty table, and various other objects. In Experiment 1, participants concurrently heard either ‘The woman will put the glass on the table’ or ‘The woman is too lazy to put the glass on the table’. Subsequently, with the scene unchanged, participants heard that the woman ‘will pick up the bottle, and pour the wine carefully into the glass.’ Experiment 2 was identical except that the scene was removed before the onset of the spoken language. In both cases, eye movements after ‘pour’ (anticipating the glass) and at ‘glass’ reflected the language-determined position of the glass, as either on the floor, or moved onto the table, even though the concurrent (Experiment 1) or prior (Experiment 2) scene showed the glass in its unmoved position on the floor. Language-mediated eye movements thus reflect the real-time mapping of language onto dynamically updateable event-based representations of concurrently or previously seen objects (and their locations).  相似文献   
198.
Hall [(2007), Philosophical Studies, 132, 109–136] offers a critique of structural equations accounts of actual causation, and then offers a new theory of his own. In this paper, I respond to Hall’s critique, and present some counterexamples to his new theory. These counterexamples are then diagnosed.
Christopher HitchcockEmail:
  相似文献   
199.
Ke-Hai Yuan 《Psychometrika》2009,74(2):233-256
When data are not missing at random (NMAR), maximum likelihood (ML) procedure will not generate consistent parameter estimates unless the missing data mechanism is correctly modeled. Understanding NMAR mechanism in a data set would allow one to better use the ML methodology. A survey or questionnaire may contain many items; certain items may be responsible for NMAR values in other items. The paper develops statistical procedures to identify the responsible items. By comparing ML estimates (MLE), statistics are developed to test whether the MLEs are changed when excluding items. The items that cause a significant change of the MLEs are responsible for the NMAR mechanism. Normal distribution is used for obtaining the MLEs; a sandwich-type covariance matrix is used to account for distribution violations. The class of nonnormal distributions within which the procedure is valid is provided. Both saturated and structural models are considered. Effect sizes are also defined and studied. The results indicate that more missing data in a sample does not necessarily imply more significant test statistics due to smaller effect sizes. Knowing the true population means and covariances or the parameter values in structural equation models may not make things easier either. The research was supported by NSF grant DMS04-37167, the James McKeen Cattell Fund.  相似文献   
200.
A connectionist model of the balance scale task is presented which exhibits developmental transitions between ‘Rule I’ and ‘Rule II’ behavior [Siegler, R. S. (1976). Three aspects of cognitive development. Cognitive Psychology,8, 481–520.] as well as the ‘catastrophe flags’ seen in data from Jansen and van der Maas [Jansen, B. R. J., & van der Maas, H. L. J. (2001). Evidence for the phase transition from Rule I to Rule II on the balance scale task. Developmental Review, 21, 450–494]. The model extends a connectionist model of this task [McClelland, J. L. (1989). Parallel distributed processing: Implications for cognition and development. In R. G. M. Morris (Ed.), Parallel distributed processing: Implications for psychology and neurobiology (pp. 8–45). Oxford: Clarendon Press] by introducing intrinsic variability into processing and by allowing the network to adapt during testing in response to its own outputs. The simulations direct attention to several aspects of the experimental data indicating that children generally show gradual change in sensitivity to the distance dimension on the balance scale. While a few children show larger changes than are characteristic of the model, its ability to account for nearly all of the data using continuous processes is consistent with the view that the transition from Rule I to Rule II behavior is typically continuous rather than discrete in nature.  相似文献   
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