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181.
Early in development, children explore and combine objects in increasingly complex ways. One manual skill, object construction, represents a major shift in how objects are explored relative to other objects. Despite recent connections with cognitive functioning such as spatial skills, the development of object construction ability has rarely been studied and its trajectory has not been adequately described. The purpose of this study was to describe the development of three types of object construction (stacking, nesting, and affixing) across 5 monthly infant visits and 7 monthly toddler visits using a longitudinal design and a large sample size. Infants (10–14 months, = 131) and toddlers drawn from the infant sample (18–24 months, = 65) were given sets of age‐appropriate toys each of which elicited at least one type of constructive play. We described success at different construction tasks and identified trends for construction skill for infant and toddler development using multilevel modeling. We found that each of the three construction actions developed in unique ways across the 10‐ to 24‐month period. Infant construction skill predicted the development of toddler skill, but toddler construction skill diverged from infant trajectories. We discuss the role of combination strategies in the development of object construction skill and how object construction could be related to other domains of development.  相似文献   
182.
Editorial     
In recent years the imperative to involve service users and carers at every level of care, service and policy development has been extended to include involving users and carers in the training of health and social care professionals. Guidance on how this is to be achieved in practice is, however, limited. This paper describes work undertaken to explore how an Approved Social Work Programme in the north of England could involve service users and carers more fully and develop an integrated approach to service user and carer involvement in this and other social work programmes. Following a review of the literature in this area, the results of a series of meetings with individual and groups of service users and carers are presented, together with a survey of ASW programmes. It then goes on to consider the implications for service user and carer involvement in the new social work degree.  相似文献   
183.
This study explored rural perspectives on same-sex marriage with a nonprobability sample (N = 156) of adult respondents recruited in a largely rural state in the upper Midwest. A new 6-item instrument with strong internal consistency (α =.943) found that support for same-sex marriage was widespread without significant differences based on relationship status, education level, rural residence, or biological sex. Sexual orientation predicted support for traditional family values and same-sex marriage which were inversely associated. Findings suggest that the presumption of rural bias and hostility toward alternative sexualities has mitigated in the upper Midwest. Social work practitioners should infer from this study that there is more to rural culture than remoteness, isolation, poverty, stigma, and conservative religious values. The malleability of rural culture may be an unrecognized strength that may provide encouragement to rural social workers advocating for and serving lesbian, gay, bisexual, and transgender (LGBT) individuals.  相似文献   
184.
185.
L'État providence Canadien est déséquilibré: leader mondial dans certains domaines de l'investissement social—plus particulièrement en soins de santé et enseignement supérieur—il traîne dans d'autres domaines de la dépense d'aide sociale, y compris les politiques de garde d'enfants. Nous constatons qu'aujourd'hui la résistance dans la plupart des régions du Canada à la politique de garde d'enfants universel a des racines historiques profondes. Elle est de fait intégré dans le cadre même du bien‐être social canadien: le contrat de citoyenneté sociale. Nous employons une approche de “bas en haut” sur l'état du bien‐être en nous concentrant sur la façon dont les acteurs collectifs, en particulier, les féministes de la première vague et leurs contemporains au sein des organisations du mouvement ouvrier, ont encadrées et caractérisé la citoyenneté sociale féminine; Nous constatons que l'exclusion de l'adhésion des femmes employées tronque les possibilités discursives par lesquelles des revendications pour des provisions universelles de bien‐être sociale pourraient être apportées. Canada's welfare state is lopsided: while leading the world in some areas of social investment—most notably health care and higher education—it is a laggard in other areas of social welfare spending, including childcare policies. We find that policy resistance to universal childcare in most regions of Canada today has deep historical roots and is, indeed, embedded into the very framework of the Canadian welfare state: the social citizenship contract. We employ a “bottom‐up” perspective on the welfare state focusing on how collective actors, in particular, first‐wave feminists and their contemporaries within labor movement organizations, framed and characterized female social citizenship in ways that excluded employed women from full membership and, in this, truncated discursive opportunities by which claims for universal welfare state provisions could be made.  相似文献   
186.
We propose a multiple imputation method to deal with incomplete categorical data. This method imputes the missing entries using the principal component method dedicated to categorical data: multiple correspondence analysis (MCA). The uncertainty concerning the parameters of the imputation model is reflected using a non-parametric bootstrap. Multiple imputation using MCA (MIMCA) requires estimating a small number of parameters due to the dimensionality reduction property of MCA. It allows the user to impute a large range of data sets. In particular, a high number of categories per variable, a high number of variables or a small number of individuals are not an issue for MIMCA. Through a simulation study based on real data sets, the method is assessed and compared to the reference methods (multiple imputation using the loglinear model, multiple imputation by logistic regressions) as well to the latest works on the topic (multiple imputation by random forests or by the Dirichlet process mixture of products of multinomial distributions model). The proposed method provides a good point estimate of the parameters of the analysis model considered, such as the coefficients of a main effects logistic regression model, and a reliable estimate of the variability of the estimators. In addition, MIMCA has the great advantage that it is substantially less time consuming on data sets of high dimensions than the other multiple imputation methods.  相似文献   
187.
A number of recent papers have focused on the problem of testing for a unit root in the case where the driving shocks may be unconditionally heteroskedastic. These papers have, however, taken the lag length in the unit root test regression to be a deterministic function of the sample size, rather than data-determined, the latter being standard empirical practice. We investigate the finite sample impact of unconditional heteroskedasticity on conventional data-dependent lag selection methods in augmented Dickey–Fuller type regressions and propose new lag selection criteria which allow for unconditional heteroskedasticity. Standard lag selection methods are shown to have a tendency to over-fit the lag order under heteroskedasticity, resulting in significant power losses in the (wild bootstrap implementation of the) augmented Dickey–Fuller tests under the alternative. The proposed new lag selection criteria are shown to avoid this problem yet deliver unit root tests with almost identical finite sample properties as the corresponding tests based on conventional lag selection when the shocks are homoskedastic.  相似文献   
188.
Simplified proofs are given of a standard result that establishes positive semi–definiteness of the difference of the inverses of two non–singular matrices, and of the extension of this result by Milliken and Akdeniz (1977) to the difference of the Moore–Penrose inverse of two singular matrices.  相似文献   
189.
To recover a low-rank structure from a noisy matrix, truncated singular value decomposition has been extensively used and studied. Recent studies suggested that the signal can be better estimated by shrinking the singular values as well. We pursue this line of research and propose a new estimator offering a continuum of thresholding and shrinking functions. To avoid an unstable and costly cross-validation search, we propose new rules to select two thresholding and shrinking parameters from the data. In particular we propose a generalized Stein unbiased risk estimation criterion that does not require knowledge of the variance of the noise and that is computationally fast. A Monte Carlo simulation reveals that our estimator outperforms the tested methods in terms of mean squared error on both low-rank and general signal matrices across different signal-to-noise ratio regimes. In addition, it accurately estimates the rank of the signal when it is detectable.  相似文献   
190.
We currently have little idea of precisely who goes for couples therapy. This is a report of the results of a validated online assessment of relationship and individual functioning based on 39,251 heterosexual, 1,022 lesbian, and 438 gay couples about to begin couples therapy. Using validated and reliable questionnaires of relationship and individual functioning, this report presents and compares, for each sexual-orientation, the percentage of couples, pre-therapy, who are coping with a variety of relationship problems. To test for the replicability of results, the sample was divided randomly into two subsamples and statistical tests were performed on each sample. Couples initiating therapy suffer from greater distress and many more co-morbidities than has been presumed in previous literature, and same-sex couples present a particular set of both strengths and challenges compared to heterosexual couples. Gay-male and lesbian couples were very different on trust and monogamy, as were heterosexual and lesbian couples. Based on this epidemiologically sized sample, the challenge to our field may be to create interventions with much larger effect sizes than we currently have.  相似文献   
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