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21.
A general latent variable model is given which includes the specification of a missing data mechanism. This framework allows for an elucidating discussion of existing general multivariate theory bearing on maximum likelihood estimation with missing data. Here, missing completely at random is not a prerequisite for unbiased estimation in large samples, as when using the traditional listwise or pairwise present data approaches. The theory is connected with old and new results in the area of selection and factorial invariance. It is pointed out that in many applications, maximum likelihood estimation with missing data may be carried out by existing structural equation modeling software, such as LISREL and LISCOMP. Several sets of artifical data are generated within the general model framework. The proposed estimator is compared to the two traditional ones and found superior.The research of the first author was supported by grant No. SES-8312583 from the National Science Foundation and by a Spencer Foundation grant. We wish to thank Chuen-Rong Chan for drawing the path diagram.  相似文献   
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In this paper, we present a BASIC program for Apple II series computers that allows the user to obtain perspective drawings of two-dimensional functions of known analytical expression. Also, we outline a procedure for obtaining perspective representations of two-dimensional arrays of data using the same program. The program should run on any computer with graphics mode with only slight modifications in the graphics commands.  相似文献   
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In some recent papers, the authors and Peter Gärdenfors have defined and studied two different kinds of formal operation, conceived as possible representations of the intuitive process of contracting a theory to eliminate a proposition. These are partial meet contraction (including as limiting cases full meet contraction and maxichoice contraction) and safe contraction. It is known, via the representation theorem for the former, that every safe contraction operation over a theory is a partial meet contraction over that theory. The purpose of the present paper is to study the relationship more finely, by seeking an explicit map between the component orderings involved in each of the two kinds of contraction. It is shown that at least in the finite case a suitable map exists, with the consequence that the relational, transitively relational, and antisymmetrically relational partial meet contraction functions form identifiable subclasses of the safe contraction functions, over any theory finite modulo logical equivalence. In the process of constructing the map, as the composition of four simple transformations, mediating notions of bottom and top contraction are introduced. The study of the infinite case remains open.  相似文献   
24.
A structural equation model is proposed with a generalized measurement part, allowing for dichotomous and ordered categorical variables (indicators) in addition to continuous ones. A computationally feasible three-stage estimator is proposed for any combination of observed variable types. This approach provides large-sample chi-square tests of fit and standard errors of estimates for situations not previously covered. Two multiple-indicator modeling examples are given. One is a simultaneous analysis of two groups with a structural equation model underlying skewed Likert variables. The second is a longitudinal model with a structural model for multivariate probit regressions.This research was supported by Grant No. 81-IJ-CX-0015 from the National Institute of Justice, by Grant No. DA 01070 from the U.S. Public Health Service, and by Grant No. SES-8312583 from the National Science Foundation. I thank Julie Honig for drawing the figures. Requests for reprints should be sent to Bengt Muthén, Graduate School of Education, University of California, Los Angeles, California 90024.  相似文献   
25.
This article seeks to identify the theoretical tools that supported Michel de Certeau's political discernment during the crisis of May 1968 in France. De Certeau's ability to elucidate the novelty and complexity of this event is linked to the intertwining of his experiences as a historian, traveller (voyageur), and Christian (specifically a Jesuit). De Certeau's articulation of a 'theology of difference' allowed him to construct the intellectual and spiritual tools that enabled a lucid discernment of May 1968. Through this theology, derived from negative theology, de Certeau made the experience of faith operative at a moment of cultural crisis. The article also analyses possibilities involved in the ‘rupture’, that is, the fracture that is implied in modernity; in the notion of an event that highlights the deficiency of language, its incapacity to establish ‘a truthful communication’ in society; and the recognition of the poetic dimension of speech, which is capable of interweaving speech and action. The May 1968 event invites these elements mutually to redefine themselves.  相似文献   
26.
COVID-19 pandemic led to introduction of lockdown measures in many countries, while in Serbia the Government also introduced the curfew by which vulnerable groups of citizens were prohibited from leaving their homes at any time. In such a situation many citizens organized to voluntarily offer their help to those in isolation, which offered a unique opportunity to examine prosocial behavior in the natural setting of global crisis. This study examined the differences between non-helpers and helpers, as well as groups of helpers who provided their help to close or unknown others, in personality (prosocial tendencies, selfishness and communal narcissism) and context-related factors (situation specific empathy and fear) of prosocial behaviors. Additionally, the study also analyzed the helping-related affect among helpers, depending on the recipient of help and personality characteristics. Results revealed that groups of helpers with different recipients of help (close persons, unknown persons or both) were not different among each other, but they were different from non-helpers. Non-helpers were more selfish and had self-focused prosocial tendencies, and they showed less empathy towards people in isolation, compared to helper groups. However, the helping-related affect depended on the recipient of help and helper's personality traits. This study confirmed some previous findings and offered novel insights into factors related to helping in crises.  相似文献   
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This review involved a systematic analysis of equivalence-based instruction (EBI) that aimed to improve food-size interventions in diverse populations. Systematic searches identified seven studies published since 2010 that met inclusion criteria. These studies were analyzed according to their participants, design, setting, content taught, training structures, training protocol, testing format, treatment integrity, and outcomes. Results showed EBI procedures for teaching food estimation skills have been mostly implemented with adults. The type of content taught in the identified studies included carbohydrate ranges, portion size with food and non-food items, measuring cups and nutritional content of calories. Majority of included studies used one-to-many training structure and simultaneous protocols for teaching stimulus relations. Five studies completed a generalization probe and three studies reported treatment integrity data. Overall, all participants demonstrated skill acquisition of novel relations between food and portion measurement aides. Recommendations for future research and clinical applications of EBI in teaching food portion estimation are presented.  相似文献   
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People hold different perspectives about how they think the world is changing or should change. We examined five of these “worldviews” about change: Progress, Golden Age, Endless Cycle, Maintenance, and Balance. In Studies 1–4 (total N = 2733) we established reliable measures of each change worldview, and showed how these help explain when people will support or oppose social change in contexts spanning sustainability, technological innovations, and political elections. In mapping out these relationships we identify how the importance of different change worldviews varies across contexts, with Balance most critical for understanding support for sustainability, Progress/Golden Age important for understanding responses to innovations, and Golden Age uniquely important for preferring Trump/Republicans in the 2016 US election. These relationships were independent of prominent individual differences (e.g., values, political orientation for elections) or context-specific factors (e.g., self-reported innovativeness for responses to innovations). Study 5 (N = 2140) examined generalizability in 10 countries/regions spanning five continents, establishing that these worldviews exhibited metric invariance, but with country/region differences in how change worldviews were related to support for sustainability. These findings show that change worldviews can act as a general “lens” people use to help determine whether to support or oppose social change.  相似文献   
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