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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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4.
Scholars in several social science disciplines scholars have argued from their respective disciplinary perspectives that income inequality has a considerable impact on economic and social performance of a nation. This essay investigates the possible impact of income inequality on 290 values and attitudes in forty industrial nations from an economic perspective. The results show that inequality has a significant impact on values and attitudes especially concerning religion and the family.  相似文献   
5.
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   
6.
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   
7.
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   
8.
An integrated, computer-based system was developed to record participants’ continuous judgment changes on a revised form of the Interpersonal Perception Task (IPT-15). Consistent with the considerable research on “thin slice” judgments, the mean latency for greater than chance accuracy confidence was just 16 s (median = 10 s) for the ten one-part scenes on the IPT. There was also a clear and strong linear trend for increasing accuracy confidence across the first 25 s of the ten one-part scenes. For the five-two-part scenes, where comparative judgments were required (e.g., which statement is truthful, which is a lie?), no clear pattern of increasing accuracy confidence was found, with mean scores hovering near chance. The utility of the new system for analyzing the time course of social judgments is discussed and the potential reasons for the contrasting results for the one-part and two-part scenes were examined.  相似文献   
9.
Fifty-three staff members currently working in residential aged care facilities located in Barcelona, Spain, were asked about the way they would react if a resident told them that he or she felt sexually attracted and had maintained sexual relationships with another resident of the same gender. Acceptance of non-heterosexual sexual orientation was a frequent answer, and around one in four professionals stated that they would try helping the resident in question, by offering a private space or giving some emotional support. However, some reactions were not consistent with a respectful approach toward sexual diversity, as, for instance, informing the resident’s family or advising the resident to keep his or her sexual orientation hidden. We highlight the importance of developing formal policies and offering formal training to staff in order to address the specific needs of older LGB people living in RACFs.  相似文献   
10.
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   
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