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1.
Summary.  Wavelet shrinkage is an effective nonparametric regression technique, especially when the underlying curve has irregular features such as spikes or discontinuities. The basic idea is simple: take the discrete wavelet transform of data consisting of a signal corrupted by noise; shrink or remove the wavelet coefficients to remove the noise; then invert the discrete wavelet transform to form an estimate of the true underlying curve. Various researchers have proposed increasingly sophisticated methods of doing this by using real-valued wavelets. Complex-valued wavelets exist but are rarely used. We propose two new complex-valued wavelet shrinkage techniques: one based on multiwavelet style shrinkage and the other using Bayesian methods. Extensive simulations show that our methods almost always give significantly more accurate estimates than methods based on real-valued wavelets. Further, our multiwavelet style shrinkage method is both simpler and dramatically faster than its competitors. To understand the excellent performance of this method we present a new risk bound on its hard thresholded coefficients.  相似文献   
2.
The authors consider the issue of map positional error, or the difference between location as represented in a spatial database (i.e., a map) and the corresponding unobservable true location. They propose a fully model‐based approach that incorporates aspects of the map registration process commonly performed by users of geographic informations systems, including rubber‐sheeting. They explain how estimates of positional error can be obtained, hence estimates of true location. They show that with multiple maps of varying accuracy along with ground truthing data, suitable model averaging offers a strategy for using all of the maps to learn about true location.  相似文献   
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The aim of this article is to analyze the difficulties in professionalizing the long-term care system in Spain. Since 2006, the new Spanish law has recognized care as a subjective right, and regulations are being designed to create a framework for its professionalization. Nowadays, family remains the most important group of providers who care for their elders, and women remain the main informal caregivers. Why do families resist using public long-term care services and professional carers included in the new law? The hypothesis highlights sociocultural factors as an obstacle to professionalization of long-term care services in addition to political and economic factors. The results show qualitative data about expectations, preferences, and discourses that women caregivers have in relation to their responsibility. The empirical material includes 25 interviews with different profiles of caregivers and six focus groups with family caregivers. The article suggests that the Spanish ideal of care is a problem for the professionalization of services because the family remains as the main provider of care—without specific skills, knowledge, and abilities.  相似文献   
5.
We characterize the set of all individual and group strategy-proof rules on the domain of all single-dipped preferences on a line. For rules defined on this domain, and on several of its subdomains, we explore the implications of these strategy-proofness requirements on the maximum size of the rules’ range. We show that when all single-dipped preferences are admissible, the range must contain two alternatives at most. But this bound changes as we consider different subclasses of single-dipped preferences: we provide examples of subdomains admitting strategy-proof rules with larger ranges. We establish exact bounds on the maximal size of strategy-proof functions on each of these domains, and prove that the relationship between the sizes of the subdomains and those of the ranges of strategy-proof functions on them need not be monotonic. Our results exhibit a sharp contrast between the structure of strategy-proof rules defined on subdomains of single-dipped preferences and those defined on subsets of single-peaked ones.  相似文献   
6.
Languages employ different strategies to mark an utterance as a polar (yes–no) question, including syntax, intonation and gestures. This study analyzes the production and perception of information-seeking questions and broad focus statements in Dutch and Catalan. These languages use intonation for marking questionhood, but Dutch also exploits syntactic variation for this purpose. A production task revealed the expected language-specific auditory differences, but also showed that gaze and eyebrow-raising are used in this distinction. A follow-up perception experiment revealed that perceivers relied greatly on auditory information in determining whether an utterance is a question or a statement, but accuracy was further enhanced when visual information was added. Finally, the study demonstrates that the concentration of several response-mobilizing cues in a sentence is positively correlated with the perceivers’ ratings of these utterances as interrogatives.  相似文献   
7.
What drives infants’ attention in complex visual scenes? Early models of infant attention suggested that the degree to which different visual features were detectable determines their attentional priority. Here, we tested this by asking whether two targets—defined by different features, but each equally salient when evaluated independently—would drive attention equally when pitted head‐to‐head. In Experiment 1, we presented 6‐month‐old infants with an array of Gabor patches in which a target region varied either in color or spatial frequency from the background. Using a forced‐choice preferential‐looking method, we measured how readily infants fixated the target as its featural difference from the background was parametrically increased. Then, in Experiment 2, we used these psychometric preference functions to choose values for color and spatial frequency targets that were equally salient (preferred), and pitted them against each other within the same display. We reasoned that if salience is transitive, then the stimuli should be iso‐salient and infants should therefore show no systematic preference for either stimulus. On the contrary, we found that infants consistently preferred the color‐defined stimulus. This suggests that computing visual salience in more complex scenes needs to include factors above and beyond local salience values.  相似文献   
8.
Those who are more emotionally invested in relationships have less power than their partners. Furthermore, less powerful individuals may attempt to equalize power imbalances by offering rewards to their partner and using sex and condom use as exchange resources. Australian young adults reported their condom use and pressured sex experiences in both romantic (n = 708) and casual (n = 118) relationships. Results showed that greater power (lower relative emotional investment) predicted more condom use among those wanting to use condoms. In casual relationships, an interaction with gender showed that women in particular used condoms more when they had more power. Power also interacted with gender for pressured sex and, unexpectedly, men who had more power experienced more pressured sex. The possibility that condom use and pressured sex have different meanings for men and women is explored.  相似文献   
9.
On the basis of theories of maternal identity development, role conflict, and childbearing motivation, the authors tested whether high educational aspirations among pregnant adolescents are related to the unwantedness of the pregnancy and whether pregnancy unwantedness leads to subsequent parenting stress and inadequacy. Longitudinal data from 100 first‐time‐pregnant, unmarried Latina adolescents (M age = 17.3 years) were analyzed. Results from structural equation path modeling confirmed these associations, with strong educational ambitions related to greater unwantedness of the pregnancy, which led to feeling trapped by parenting at 6 months postpartum, which in turn was related to unaffectionate parenting and feeling inadequate in mothering at 1 year postpartum. The potential long‐term negative consequences of high educational aspirations for pregnant adolescents' adjustment to parenting are discussed.  相似文献   
10.
Family support policies (FSP) refer to government policies that promote the well-being of families with children (e.g. job-protected paid leave, cash transfers, childcare). We developed an initial conceptual and theoretical framework of FSP and conducted a realist-scoping review to document the state of evidence regarding the influence of FSP on three child outcomes: poverty, development, and health. Based on the contexts and mechanisms through which FSP are hypothesized to affect child outcomes, we constructed a framework to guide a search of five electronic databases (OVID, ProQuest, PubMed, Scopus, and Web of Knowledge). We analysed articles meeting our inclusion criteria (i.e. conceptualized FSP as a function of the welfare state; conceptualized child poverty, development, and health as outcomes; and conducted empirical analyses) in relation to our mechanisms and thematic concerns (context, developmental periods, and differential impacts). A total of 22 studies met our inclusion criteria, which tested 25 independent child outcomes. Our findings identified initial mechanisms that explain the relationship between FSP and child outcomes through (1) increasing parents’ basic capabilities, (2) shaping parents’ childcare options, and (3) influencing parental leave-taking and shifting beliefs about gender relationships in the home and workplace. Future work will be to test these mechanisms and framework through a realist synthesis.  相似文献   
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