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381.
Robert J. Deltete 《Zygon》2008,43(3):627-637
The essay “Physique de croyant” is an important statement of Pierre Duhem's position on the relation between his science and his religion. Duhem trod a difficult path, some might say an impossible one, in Republican France because he was both a physicist and a devout Catholic. In this essay, using “Physique de croyant” as a touchstone, I explore the way in which he tried to reconcile his conflicting allegiances. There are several strands in Duhem's strategy that need to be teased out. First, Duhem sought to defend his science against the charge that it was materialist and atheist. He did this with his claim, usually called the autonomy thesis, that physics and metaphysics are fundamentally different enterprises—that physics, properly conducted, has no metaphysical implications and requires no metaphysical support. This did not deny metaphysics its rightful territory. Second, Duhem used his segregationist position to defend the Roman Catholic Church against the assaults of the positivist scientism then in favor with the Republicans. Third, he also sought to protect his science against fellow Catholics who wanted to use it for polemical purposes. I develop and evaluate these lines of defense.  相似文献   
382.
Cervical cancer is the second most common cancer in women globally. A computer aided cervical disease diagnosis system that can relieve pressure on medical experts and save the cost is proposed. To implement our approach in the reality of cervical diseases diagnosis, a multi-modal framework is designed for three kinds of cervical diseases diagnosis that integrates uterine cervix images, Thinprep Cytology Test, human papillomavirus test, and patients’ age. However, too many features increase memory storage costs and computational costs, and it affects the spread of this system in poor areas. Feature selection not only eliminates redundant or irrelevant features but also finds the factors that influence the disease most first is performed in multi-modal frameworks for cervical diseases diagnosis. The detailed process of the method is as follows: first, according the representative color, an efficient image segmentation algorithm is developed; then from three different types of segmented images, we extract color features and texture features for interpreting uterine cervix images; next, Boruta algorithm is applied to feature selection; finally, the performance of Random Forests that utilizes selected features for cervical disease diagnosis is investigated. In the experiment, the proposed multi-modal diagnostic approach gives the final diagnosis for three different kinds of cervical diseases with 83.1% accuracy, which significantly outperforms methods using any single source of information alone. The validation cohort is applied to validate the efficiency of our method, and the performance of random forest obtained by using only 1.2% of features is like or even better than using 100% of features.  相似文献   
383.
Cognitive diagnosis models (CDMs) have been used as psychometric tools in educational assessments to estimate students’ proficiency profiles. However, most CDMs assume that all students adopt the same strategy when approaching problems in an assessment, which may not be the case in practice. This study develops a generalized multiple-strategy CDM for dichotomous response data. The proposed model provides a unified framework to accommodate various condensation rules (e.g., conjunctive, disjunctive, and additive) and different strategy selection approaches (i.e., probability-matching, over-matching, and maximizing). Model parameters are estimated using the marginal maximum likelihood estimation via expectation-maximization algorithm. Simulation studies showed that the parameters of the proposed model can be adequately recovered and that the proposed model was relatively robust to some types of model misspecifications. A set of real data was analysed as well to illustrate the use of the proposed model in practice.  相似文献   
384.
In the present exploratory study based on 7 subjects, we examined the composition of magnetoencephalographic (MEG) brain oscillations induced by the presentation of an auditory, visual, and audio-visual stimulus (a talking face) using an oddball paradigm. The composition of brain oscillations were assessed here by analyzing the probability-classification of short-term MEG spectral patterns. The probability index for particular brain oscillations being elicited was dependent on the type and the modality of the sensory percept. The maintenance of the integrated audio-visual percept was accompanied by the unique composition of distributed brain oscillations typical of auditory and visual modality, and the contribution of brain oscillations characteristic for visual modality was dominant. Oscillations around 20 Hz were characteristic for the maintenance of integrated audio-visual percept. Identifying the actual composition of brain oscillations allowed us (1) to distinguish two subjectively/consciously identical mental percepts, and (2) to characterize the types of brain functions involved in the maintenance of the multi-sensory percept.  相似文献   
385.
The regression trunk approach (RTA) is an integration of regression trees and multiple linear regression analysis. In this paper RTA is used to discover treatment covariate interactions, in the regression of one continuous variable on a treatment variable withmultiple covariates. The performance of RTA is compared to the classical method of forward stepwise regression. The results of two simulation studies, in which the true interactions are modeled as threshold interactions, show that RTA detects the interactions in a higher number of cases (82.3% in the first simulation study, and 52.3% in the second) than stepwise regression (56.5% and 20.5%). In a real data example the final RTA model has a higher cross-validated variance-accounted-for (29.8%) than the stepwise regression model (12.5%). All of these results indicate that RTA is a promising alternative method for demonstrating differential effectiveness of treatments. Supported by The Netherlands Organization for Scientific Research (NWO), grant 030-56403 to Jacqueline Meulman for the Pioneer project “Subject-Oriented Multivariate Analysis,” and grant 451-02-058 to Elise Dusseldorp for the Veni project “Modeling interaction effects as small trees in regression and classification.” We thank Bram Bakker for making the data of his doctoral dissertation available, and David Hand, Jerome Friedman, Bart Jan van Os, Philip Spinhoven, and the anonymous reviewers for their helpful suggestions. Special thanks are due to Lawrence Hubert.  相似文献   
386.
Three-Mode Component Analysis with Crisp or Fuzzy Partition of Units   总被引:1,自引:0,他引:1  
A new methodology is proposed for the simultaneous reduction of units, variables, and occasions of a three-mode data set. Units are partitioned into a reduced number of classes, while, simultaneously, components for variables and occasions accounting for the largest common information for the classification are identified. The model is a constrained three-mode factor analysis and it can be seen as a generalization of the REDKM model proposed by De Soete and Carroll for two-mode data. The least squares fitting problem is mathematically formalized as a constrained problem in continuous and discrete variables. An iterative alternating least squares algorithm is proposed to give an efficient solution to this minimization problem in the crisp and fuzzy classification context. The performances of the proposed methodology are investigated by a simulation study comparing our model with other competing methodologies. Different procedures for starting the proposed algorithm have also been tested. A discussion of some interesting differences in the results follows. Finally, an application to real data illustrates the ability of the proposed model to provide substantive insights into the data complexities.  相似文献   
387.
388.
Recent literature suggests that different ‘styles’ of homicide will most appropriately be reflected in the different types of behaviours committed by offenders during the crime. In the last few years, there has been a move to standardise classification systems of single homicides and establish their cross‐national generalisability. Literature on serial homicide to date has mostly centred on homicides occurring in the US. However, national differences due to factors such as culture, national identity, political, and socio‐economic circumstances may decrease the applicability of these models or certain aspects thereof in other countries and thus must be evaluated. The present study tested the applicability in the South African context of a recently developed US‐based serial homicide crime scene classification framework. Specifically, this study compared the thematic differentiation in planning and violent behaviours that the offenders engage in and how this differentiation compares with that in the US. The sample consisted of 25 homicides that were in total responsible for the murder of 267 victims. Results indicated that overall, the framework is useful and applicable in the South African sample, but important environmental and contextual constraints must be taken into account. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
389.
以三套分别含有按照解题方法可以分为二类、三类、四类的物理学科问题分类实验材料,对济南市6所中学3个年级766名中学生进行研究,结果表明:不同年级、不同学业水平学生分类表征层次的差异显著,呈现随年级升高而升高的趋势,学优生的水平明显高于学困生,学优生更多地倾向内在分类表征;随着分类任务的类别数量增多,更多学生倾向外在分类表征;不同性别学生的分类表征层次没有显著差异;不同物理学科问题分类表征层次学生的物理成绩之间存在显著差异。  相似文献   
390.
Theological libraries in the Caribbean have suffered from invisibility, so this study aims to bring these libraries to the fore. It presents key features of the libraries and seeks to determine if these are influenced by the libraries’ denominational affiliation, geographic location, and size. Geographically speaking, the target area was twenty-nine Caribbean territories. Data was gathered using a questionnaire containing mainly open-ended questions in English and Spanish, which was mostly administered face-to-face. The general results are offered first: the number of libraries found, their geographic location—whether in the English, Spanish and Dutch-speaking Caribbean—their denominations, and their size. These results are followed by a more detailed presentation focusing on classification schemes, subject headings, automation, and staffing at the supervisory level. The findings are then analyzed by denomination, location, and size. The article ends with a discussion of the results, comparing theological libraries in the Caribbean with theological libraries in the United States, Asia, and Europe. The study concludes that denomination and location have not affected the findings; but size has to some extent. Also, in some areas, Caribbean theological libraries resemble those in North America, while in others they resemble those in Asia and Europe.  相似文献   
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