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31.
UNESCO is an intergovernmental organization with 193 Member States. It is concerned with a broad range of issues regarding education, science and culture. It is the only UN organisation with a mandate in science. Since 1993 it is addressing ethics of science and technology, with special emphasis on bioethics. One major objective of the ethics programme is the development of international normative standards. This is particularly important since many Member States only have a limited infrastructure in bioethics, lacking expertise, educational programs, bioethics committees and legal frameworks. UNESCO has recently adopted the Universal Declaration on Bioethics and Human Rights. The focus of current activities is now on implementation of this Declaration. Three activities are discussed that aim at improving and reinforcing the ethics infrastructure in relation to science and technology: the Global Ethics Observatory, the Ethics Education Programme and the Assisting Bioethics Committees project.  相似文献   
32.
We aimed to explain the influence of family involvement on feelings of burnout among employees who combine work and family tasks. As proxies for family involvement, we used the family structure (partner, number and age of children) and family tasks (e.g. hours spent on household chores). We compared conflict theory and enrichment theory, and investigated how well they explain the relationship between family involvement and feelings of burnout. Based on a sample of 1046 employees at 30 Dutch organizations, the results showed that the presence of young children and doing more household chores were positively related to feelings of burnout, whereas having children reduced employees’ feelings of burnout. We also investigated interaction effects of gender and gender-role norms. We conclude that family life can reduce work-related burnout and that for men, the relationship between family involvement and feelings of burnout differs depending on whether they have traditional or modern gender-role norms.  相似文献   
33.
The use of Candecomp to fit scalar products in the context of INDSCAL is based on the assumption that the symmetry of the data matrices involved causes the component matrices to be equal when Candecomp converges. Ten Berge and Kiers gave examples where this assumption is violated for Gramian data matrices. These examples are believed to be local minima. It is now shown that, in the single-component case, the assumption can only be violated at saddle points. Chances of Candecomp converging to a saddle point are small but still nonzero.  相似文献   
34.
Background Despite the renewed interest in citizenship education, relatively little is known about effective ways to realize citizenship education in the classroom. In the literature on citizenship education, dialogue is considered to be a crucial element. However, there is very little, if any, empirical research into the different ways to stimulate dialogue. Aim The main aim of this study is to arrive at an understanding of how citizenship education can be integrated in history classes. The focus is on the effect of a dialogic approach to citizenship education on students' ability to justify an opinion on moral issues. Sample Four hundred and eighty‐two students in the eighth grade of secondary education. Methods Two curriculum units for dialogic citizenship education were developed and implemented. The two curriculum units differed in the balance between group work and whole‐class teaching. Students' ability to justify an opinion was assessed by means of short essays written by students on a moral issue. The effectiveness of both curriculum units was compared with regular history classes. Results Students who participated in the lessons for dialogic citizenship education were able to justify their opinion better than students who participated in regular history lessons. The results further show a positive effect of the amount of group work involved. Conclusion The results of this study indicate that a dialogic approach to citizenship education as an integral part of history classes helps students to form a more profound opinion about moral issues in the subject matter. In addition, group work seems to be a more effective method to implement dialogue in the classroom than whole‐class teaching.  相似文献   
35.
Varimax rotation consists of iteratively rotating pairs of columns of a matrix to a maximal sum (over columns) of variances of squared elements of the matrix. Without loss of optimality, the two rotated columns can be permuted and/or reflected. Although permutations and reflections are harmless for each planar rotation per se, they can be harmful in Varimax rotation. Specifically, they often give rise to the phenomenon that certain pairs of columns are consistently skipped in the iterative process, whence Varimax will be terminated at a nonstationary point. The skipping phenomenon is demonstrated, and it is shown how to prevent it.The author is obliged to Henk Kiers for commenting on a previous draft.  相似文献   
36.
Green solved the problem of least-squares estimation of several criteria subject to the constraint that the estimates have an arbitrary fixed covariance or correlation matrix. In the present paper an omission in Green's proof is discussed and resolved. Furthermore, it is shown that some recently published solutions for estimating oblique factor scores are special cases of Green's solution for the case of fixed covariance matrices.  相似文献   
37.
Kruskal, Harshman and Lundy have contrived a special 2 × 2 × 2 array to examine formal properties of degenerate Candecomp/Parafac solutions. It is shown that for this array the Candecomp/Parafac loss has an infimum of 1. In addition, the array will be used to challenge the tradition of fitting Indscal and related models by means of the Candecomp/Parafac process.  相似文献   
38.
Kroonenberg and de Leeuw (1980) have developed an alternating least-squares method TUCKALS-3 as a solution for Tucker's three-way principal components model. The present paper offers some additional features of their method. Starting from a reanalysis of Tucker's problem in terms of a rank-constrained regression problem, it is shown that the fitted sum of squares in TUCKALS-3 can be partitioned according to elements of each mode of the three-way data matrix. An upper bound to the total fitted sum of squares is derived. Finally, a special case of TUCKALS-3 is related to the Carroll/Harshman CANDECOMP/PARAFAC model.  相似文献   
39.
Centering a matrix row-wise and rescaling it column-wise to a unit sum of squares requires an iterative procedure. It is shown that this procedure converges to a stable solution. This solution need not be centered row-wise if the limiting point of the interations is a matrix of rank one. The results of the present paper bear directly on several types of preprocessing methods in Parafac/Candecomp.  相似文献   
40.
Harshman's DEDICOM model providesa framework for analyzing square but asymmetric materices of directional relationships amongn objects or persons in terms of a small number of components. One version of DEDICOM ignores the diagonal entries of the matrices. A straight-forward computational solution for this model is offered in the present paper. The solution can be interpreted as a generalized Minres procedure suitable for handing asymmetric matrices.  相似文献   
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