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41.
The semiparametric estimators of time varying long memory parameter are investigated for locally stationary long memory processes. The GPH estimator and the local Whittle estimator are considered. Under some mild regularity assumptions, the weak consistency and the asymptotic normality of the estimators are obtained. The finite sample performance of the estimators is discussed through a small simulation study.  相似文献   
42.
The main goal of this work is to consider the detrended fluctuation analysis (DFA), proposed by Peng et al. [Mosaic organization of DNA nucleotides, Phys. Rev. E. 49(5) (1994), 1685–1689]. This is a well-known method for analysing the long-range dependence in non-stationary time series. Here we describe the DFA method and we prove its consistency and its exact distribution, based on the usual i.i.d. assumption, as an estimator for the fractional parameter d. In the literature it is well established that the nucleotide sequences present long-range dependence property. In this work, we analyse the long dependence property in view of the autoregressive moving average fractionally integrated ARFIMA(p, d, q) processes through the analysis of four nucleotide sequences. For estimating the fractional parameter d we consider the semiparametric regression method based on the periodogram function, in both classical and robust versions; the semiparametric R/S(n) method, proposed by Hurst [Long term storage in reservoirs, Trans. Am. Soc. Civil Eng. 116 (1986), 770–779] and the maximum likelihood method (see [R. Fox and M.S. Taqqu, Large-sample properties of parameter estimates for strongly dependent stationary Gaussian time series, Ann. Statist. 14 (1986), 517–532]), by considering the approximation suggested by Whittle [Hypothesis Testing in Time Series Analysis (1953), Hafner, New York].  相似文献   
43.
We consider the problem of modelling a long-memory time series using piecewise fractional autoregressive integrated moving average processes. The number as well as the locations of structural break points (BPs) and the parameters of each regime are assumed to be unknown. A four-step procedure is proposed to find out the BPs and to estimate the parameters of each regime. Its effectiveness is shown by Monte Carlo simulations and an application to real traffic data modelling is considered.  相似文献   
44.
The sieve bootstrap (SB) prediction intervals for invertible autoregressive moving average (ARMA) processes are constructed using resamples of residuals obtained by fitting a finite degree autoregressive approximation to the time series. The advantage of this approach is that it does not require the knowledge of the orders, p and q, associated with the ARMA(p, q) model. Up until recently, the application of this method has been limited to ARMA processes whose autoregressive polynomials do not have fractional unit roots. The authors, in a 2012 publication, introduced a version of the SB suitable for fractionally integrated autoregressive moving average (FARIMA (p,d,q)) processes with 0<d<0.5 and established its asymptotic validity. Herein, we study the finite sample properties this new method and compare its performance against an older method introduced by Bisaglia and Grigoletto in 2001. The sieve bootstrap (SB) method is a numerically simpler alternative to the older method which requires the estimation of p, d, and q at every bootstrap step. Monte-Carlo simulation studies, carried out under the assumption of normal, mixture of normals, and exponential distributions for the innovations, show near nominal coverages for short-term and long-term SB prediction intervals under most situations. In addition, the sieve bootstrap method yields better coverage and narrower intervals compared to the Bisaglia–Grigoletto method in some situations, especially when the error distribution is a mixture of normals.  相似文献   
45.
Most of the long memory estimators for stationary fractionally integrated time series models are known to experience non‐negligible bias in small and finite samples. Simple moment estimators are also vulnerable to such bias, but can easily be corrected. In this article, the authors propose bias reduction methods for a lag‐one sample autocorrelation‐based moment estimator. In order to reduce the bias of the moment estimator, the authors explicitly obtain the exact bias of lag‐one sample autocorrelation up to the order n−1. An example where the exact first‐order bias can be noticeably more accurate than its asymptotic counterpart, even for large samples, is presented. The authors show via a simulation study that the proposed methods are promising and effective in reducing the bias of the moment estimator with minimal variance inflation. The proposed methods are applied to the northern hemisphere data. The Canadian Journal of Statistics 37: 476–493; 2009 © 2009 Statistical Society of Canada  相似文献   
46.
Cash‐for‐care (CfC) schemes are monetary transfers to people in need of care who can use them to organize their own care arrangements. Mostly introduced in the 1990s, these schemes combine different policy objectives, as they can aim at (implicitly or explicitly) supporting informal caregivers as well as increasing user choice in long‐term care or even foster the formalization of care relations and the creation of care markets. This article explores from a comparative perspective, how CfC schemes, within broader long‐term care policies, envision, frame, and aim to condition informal care, if different models of relationships between CfC and informal care exist and how these have persisted or changed over time and into which directions. Building on the scholarly debate on familialization vs. defamilialization policies, the paper proposes an analytical framework to investigate the trajectories of seven European countries over a period of 20 years. The results show that, far from being simply instruments of supported familialism, CfC schemes have contributed to a turn towards “optional familialism through the market,” according to which families are encouraged to provide family care and are (directly or indirectly) given alternatives through the provision of market care.  相似文献   
47.
While public expenditure on health care and long‐term care (LTC) has been monitored for many years in European countries, far less attention has been paid to the financial consequences for older people of private out‐of‐pocket (OOP) expenditure necessary to access such care. Employing representative cross‐sectional data on the elderly populations of 11 European countries in 2004 from the Survey of Health, Ageing and Retirement in Europe (SHARE), we find that OOP payments for health care and LTC are very common among the elderly across European countries and such expenditures impact significantly on disposable income: up to 95 per cent of the elderly make OOP payments for health care and 5 per cent for LTC, resulting in income reductions of between 5 and 10 per cent, respectively. Failure to prevent financial ruin, as a consequence of excessive OOP payments, is evident in 0.7 per cent of elderly households utilizing health care and 0.5 per cent of elderly households utilizing LTC. Those particularly concerned are the poor, women and the very old.  相似文献   
48.
中国经济发展机制及其解释   总被引:1,自引:0,他引:1  
本文从中国经济现实出发 ,阐释了以土地集体所有、个人使用的农业制度为基础的中国经济 ,在以消除剩余劳动力为特征的经济发展过程中可能表现出来的若干基本趋势 ,从而提出了中国经济长期发展的一种可能机制  相似文献   
49.
Abstract

Making use of a formulation by Rosalie Kane of the ingredients necessary to “a good life” for residents of homes for the aged and other long term care facilities, the role of the social worker in insuring the presence of these ingredients is discussed. Included is an analysis of the responsibilities and tasks of the social worker which must be carried and fulfilled in order that social workers make appropriate contributions to “the good life.”  相似文献   
50.
No abstract available for this article.  相似文献   
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