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61.
Phenotyping the system of prejudice and discrimination, which gives preference to European physical characteristics and devalues those of Amerindians, Africans, and Asians, affects the lives of many Latinos in the United States. This study examines the impact of phenotyping on academic and employment outcomes among Latino adolescents/young adults. Outcomes examined include the odds of graduating from high school, finding full-time employment after completing high school, and attending college. Socioeconomic status (measured at individual and school levels), family structure, quality of parent–child relationships, immigrant generational status, and other measures are included as controls. Multilevel modeling and logistic regression are utilized as analytical tools. Results indicate that, among Latinos, light skin and blue eyes are associated with better academic outcomes than having dark skin and brown eyes, while those with darker skin enter the labor market earlier than their light-skinned co-ethnics.  相似文献   
62.
Novel materials with unique or enhanced properties relative to conventional materials are being developed at an increasing rate. These materials are often referred to as advanced materials (AdMs) and they enable technological innovations that can benefit society. Despite their benefits, however, the unique characteristics of many AdMs, including many nanomaterials, are poorly understood and may pose environmental safety and occupational health (ESOH) risks that are not readily determined by traditional risk assessment methods. To assess these risks while keeping up with the pace of development, technology developers and risk assessors frequently employ risk‐screening methods that depend on a clear definition for the materials that are to be assessed (e.g., engineered nanomaterial) as well as a method for binning materials into categories for ESOH risk prioritization. The term advanced material lacks a consensus definition and associated categorization or grouping system for risk screening. In this study, we aim to establish a practitioner‐driven definition for AdMs and a practitioner‐validated framework for categorizing AdMs into conceptual groupings based on material characteristics. Results from multiple workshops and interviews with practitioners provide consistent differentiation between AdMs and conventional materials, offer functional nomenclature for application science, and provide utility for future ESOH risk assessment prioritization. The definition and categorization framework established here serve as a first step in determining if and when there is a need for specific ESOH and regulatory screening for an AdM as well as the type and extent of risk‐related information that should be collected or generated for AdMs and AdM‐enabled technologies.  相似文献   
63.
The volume and variety of manufactured chemicals is increasing, although little is known about the risks associated with the frequency and extent of human exposure to most chemicals. The EPA and the recent signing of the Lautenberg Act have both signaled the need for high-throughput methods to characterize and screen chemicals based on exposure potential, such that more comprehensive toxicity research can be informed. Prior work of Mitchell et al. using multicriteria decision analysis tools to prioritize chemicals for further research is enhanced here, resulting in a high-level chemical prioritization tool for risk-based screening. Reliable exposure information is a key gap in currently available engineering analytics to support predictive environmental and health risk assessments. An elicitation with 32 experts informed relative prioritization of risks from chemical properties and human use factors, and the values for each chemical associated with each metric were approximated with data from EPA's CP_CAT database. Three different versions of the model were evaluated using distinct weight profiles, resulting in three different ranked chemical prioritizations with only a small degree of variation across weight profiles. Future work will aim to include greater input from human factors experts and better define qualitative metrics.  相似文献   
64.
This article presents a framework informed by two disciplines, Social Innovation and Applied Ethics, to be used in an ongoing analysis of territorial democratic systems. It aims to combine Social Innovation and Applied Ethics analysis to better understand the socio-political regeneration process in Iceland initiated with the 2008 global crisis. This crisis, particularly in Iceland had an economic and political aspect affecting the self-understanding of the territories as a whole, but in the Basque Country at present, it also deals with the current peace process to settle down political violence and its causes. In both cases there are deep underlying value issues. Nevertheless, this article introduces only the results obtained in Iceland. While its democratic system has proven to be able to contest the causes of the crisis, there is no definitive evidence that the re-examination process that was opened in October 2008 is resolved yet.  相似文献   
65.
66.
A simple procedure to tighten the Lagrangian bounds is proposed. The approach is interpreted in two ways. First, it can be seen as a reformulation of the original problem aimed to split the resulting Lagrangian problem into two subproblems. Second, it can be considered as a search for a tighter estimation of the penalty term arising in the Lagrangian problem. The new bounds are illustrated by a small example and studied numerically for a class of the generalized assignment problems.  相似文献   
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68.
Rates of convergence of Bayesian nonparametric procedures are expressed as the maximum between two rates: one is determined via suitable measures of concentration of the prior around the “true” density f0, and the other is related to the way the mass is spread outside a neighborhood of f0. Here we provide a lower bound for the former in terms of the usual notion of prior concentration and in terms of an alternative definition of prior concentration. Moreover, we determine the latter for two important classes of priors: the infinite–dimensional exponential family, and the Pólya trees.  相似文献   
69.
A new method for analyzing high-dimensional categorical data, Linear Latent Structure (LLS) analysis, is presented. LLS models belong to the family of latent structure models, which are mixture distribution models constrained to satisfy the local independence assumption. LLS analysis explicitly considers a family of mixed distributions as a linear space, and LLS models are obtained by imposing linear constraints on the mixing distribution.LLS models are identifiable under modest conditions and are consistently estimable. A remarkable feature of LLS analysis is the existence of a high-performance numerical algorithm, which reduces parameter estimation to a sequence of linear algebra problems. Simulation experiments with a prototype of the algorithm demonstrated a good quality of restoration of model parameters.  相似文献   
70.
Summary Strasser (1981) introduced approximately maximum likelihood estimators (AMLE's) and found a condition equivalent to strong consistency of all AMLE's. Here a condition weaker than that of Strasser is proved to be equivalent to the usual consistency of all AMLE's. Under an additional regularity this condition is shown to be doubly equivalent, which means that it is equivalent to consistency, and its contrary is equivalent to inconsistency of all AMLE's. The doubly equivalent conditions are important—we present an example where MLE is strongly consistent but some AMLE's are inconsistent. It is proved that the additional regularity can be reduced to the finiteness of an observations entropy. All results are motivate and illustrated by examples. Supported by CSAS grant N. 17503.  相似文献   
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