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101.
This paper is concerned with cases in which patients who have been well established in treatment decide to end it prematurely. In examining the issue among my patients who left against my advice, I isolated in some of them a number of common traits, of which the existence of a long-standing idealizing transference was central. Four of these cases are presented, including two in which the resistance was successfully penetrated and two in which it was not and the patient left treatment. The definition of premature termination is seen in the context of that of a complete analysis.  相似文献   
102.
Over the first years of life, infants gradually develop the ability to retrieve their memories across cue and contextual changes. Whereas maturational factors drive some of these developments in memory ability, experiences occurring within the learning event may also impact infants' ability to retrieve memories in new situations. In 2 experiments we examined whether it was possible to facilitate 12‐month‐old infants' generalization of learning in the deferred imitation paradigm by varying experiences before or during the demonstration session, or during the retention interval. In Experiment 1, altering the length, timing, or variability of training had no impact on generalization; infants showed a low, but consistent level of memory retrieval. In Experiment 2, infants who experienced a unique context for encoding and retrieval exhibited generalization; infants who experienced the context prior to the demonstration session, or during the retention interval, did not. Specificity is a robust feature of infant memory and is not substantially altered by encoding experiences in an observational learning paradigm. Previous history with a learning environment can, however, impact the flexibility of memory retrieval.  相似文献   
103.
The authors provide an overview of optimal scaling results for the Metropolis algorithm with Gaussian proposal distribution. They address in more depth the case of high‐dimensional target distributions formed of independent, but not identically distributed components. They attempt to give an intuitive explanation as to why the well‐known optimal acceptance rate of 0.234 is not always suitable. They show how to find the asymptotically optimal acceptance rate when needed, and they explain why it is sometimes necessary to turn to inhomogeneous proposal distributions. Their results are illustrated with a simple example.  相似文献   
104.
Unfortunately many of the numerous algorithms for computing the comulative distribution function (cdf) and noncentrality parameter of the noncentral F and beta distributions can produce completely incorrect results as demonstrated in the paper by examples. Existing algorithms are scrutinized and those parts that involve numerical difficulties are identified. As a result, a pseudo code is presented in which all the known numerical problems are resolved. This pseudo code can be easily implemented in programming language C or FORTRAN without understanding the complicated mathematical background. Symbolic evaluation of a finite and closed formula is proposed to compute exact cdf values. This approach makes it possible to check quickly and reliably the values returned by professional statistical packages over an extraordinarily wide parameter range without any programming knowledge. This research was motivated by the fact that a very useful table for calculating the size of detectable effects for ANOVA tables contains suspect values in the region of large noncentrality parameter values compared to the values obtained by Patnaik’s 2-moment central-F approximation. The cause is identified and the corrected form of the table for ANOVA purposes is given. The accuracy of the approximations to the noncentral-F distribution is also discussed. The authors wish to thank Mr. Richárd Király for his preliminary work. The authors are grateful to the Editor and Associate Editor of STCO and the unknown reviewers for their helpful suggestions.  相似文献   
105.
A new sampling inspection system involving normal and tightened plans is presented. Performance measures are developed. The average sample number of the newly developed system is compared with those of existing plans. Procedures are indicated an tables are constructed for designing the system indexed by various combinations of parameters.  相似文献   
106.
Maints auteurs ont affirmé que la race et le sexe repreésentent des bases de fractions de classe en ce sens que leur construction sociale permet à des segments d'une classe de se constituer à partir de caractéristiques liées à la race et au sexe. Cependant, les études ernpiriques antérieures tendent à considérer seulernent la race et le sexe comme des facteurs de fractionnernent au sein de la classe ouvrière seulement. À l'aide des données du recensement de 1986, cette communication analyse lea effets interactifs de la race et du sexe sur le revenu considéré comme facteur de fractionnement des classes. Les recherches de l'auteur indiquent que les effets produits par le groupement par race et par sexe sont inégaux en ce qui trait au revenu, les hommes gagnant davantage que les femmes tout en étant davantage ‘fractionnés’ par le revenu que les femmes. Lorsqu'on fait abstraction des différences de revenu entre classes, la race et le sexe demeurent des facteurs explicatifs importants du niveau de revenu, bien que leurs effets soient plus marqués chez les cadres, les professionnels et les ouvriers. L'écart entre les sexes est plus prononcé, mais la race demeure importante comme facteur de fractionnement au niveau des revenus des homrnes, měme après correction pour tenir cornpte d'autres variables. L'auteur affirme que l'assimilation des relations de sexe et de race aux relations entre classes est insatisfaisante et qu'il existe de sérieuses considérations théoriques pour considérer que les causes des inégalités entre les sexes et les races se trouvent non seulement à l'intérieur du domaine de la production, mais également à l'extérieur de celui-ci. The literature has argued that race and gender are bases of class fractions in that their social construction enables segments of a class to be constituted on racialized and gender-linked characteristics. However, previous empirical works tend to consider race or gender as fractionalizing the working class only. Using the 1986 Census data, this paper analyses the interactive effects of race and gender on earnings as grounds of fractionalizing classes. The findings indicate that race and gender groupings produce unequal effects on earnings: males have an income advantage over females, but race fractionalizes the earnings of men to a greater extent than for women. When inter-class differences in earnings are removed, race and gender remain important in explaining earnings, although their effects are stronger among the managerial, the professsional, and the working class. The gender gap is more pronounced, but race remains important in fractionalizing the earnings of men even after controlling for other variables. The paper argues that it is insufficient to subsume gender and race relations under class relations, and that there are compelling theoretical grounds to consider gender and race inequality as having roots both within and outside the sphere of production.  相似文献   
107.
The work-welfare nexus is essential in all social policy regimes. The question is in what situations individuals should be entitled to social welfare benefits and in which situations they should be obliged to work. Social welfare law and administrative practices define mechanisms that separate the deserving poor from people able to work. This article analyses the functions and character of these "separation mechanisms" in Sweden during three periods in history: a) in rural society in the late 19th century; b) in industrial society during the successful years of the Swedish model from World War II until the late 1970s; and c) the present, including the period of welfare retrenchment and reconsideration since the early 1980s. The conclusion is that Swedish social policy has always been strongly work-oriented, but the specific form and content of the work ethic has varied under the influence of different ideologies and handled in different social policy institutions. Under specific conditions the work line has been either generous or restrictive and it has been based on structural attempts to improve the opportunities to work as well as on attempts to strongly pressure the individual to work. The work line of today is seen as an interesting attempt to combine an effort to create good work through improved work conditions and an effort to reinforce elements of work enforcement in the social insurance system.  相似文献   
108.
109.
The problem of determining the number of multi-type protection devices and their locations on electrical supply tree networks with subtree dependency is investigated. The aim is to reduce the amount of inconvenience caused to customers that are affected by any given fault on the networks. An appropriate implementation of tabu search is proposed. We exploit a variable neighborhood and a soft aspiration level, and we embed a data structure and reduction tests into the search to speed up the process. Computational tests are performed on randomly generated electrical tree networks varying in size and branch complexity with encouraging results.  相似文献   
110.
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