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381.
The audit fees available since 2005 as a consequence of the Bilanzrechtsreformgesetz (commercial code reform act) show an extremely high supplier concentration on the German audit market of publicly listed companies. This justifies the assumption of audit fees above perfect market equilibrium prices. However, the complete collection and multivariate regression analysis of all relevant audit fee and client data document a 24 % decrease in audit fees in 2005 and an average 15 % decrease in the two subsequent years due to auditor changes. This can be interpreted as an indicator for price competition. In addition, the audit fee data shows that the audit fee decreases are only partially compensated by subsequent increases. As a consequence, there is no evidence for lowballing at present. Further time series are necessary to show if the current trend is sustainable.  相似文献   
382.
The potential for cannibalization of new product sales by remanufactured versions of the same product is a central issue in the continuing development of closed‐loop supply chains. Practitioners have no fact‐based information to guide practice at firms and academics have no studies available to use as the basis for assumptions in models. We address the cannibalization issue by using auctions to determine consumers’ willingness to pay (WTP) for both new and remanufactured products. The auctions also allow us to better understand the potential impact of offering new and remanufactured products at the same time, which provides us insights into the potential for new product cannibalization. Our results indicate that, for the consumer and commercial products auctioned, there is a clear difference in WTP) for new and remanufactured goods. For the consumer product, there is scant overlap in bidders between the new and remanufactured products, leading us to conclude that the risk of cannibalization in this case is minimal. For the commercial product, there is evidence of overlap in bidding behavior, exposing the potential for cannibalization.  相似文献   
383.
The use of microcomputers to process census data in developing countries is discussed. Specifically, the authors describe the Integrated Microcomputer Processing System (IMPS) developed by the U.S. Bureau of the Census and focus "on the recent experience of Burkina Faso and Senegal in using microcomputers. A summary is given of the use of IMPS by an increasing number of countries. Additionally, this paper describes the latest enhancements and future plans for IMPS. It concludes with some thoughts on the use of microcomputers in the areas of data collection and processing, as well as in the use and dissemination of census data."  相似文献   
384.
The contract manufacturing industry has grown rapidly in recent years as firms have increasingly outsourced production to reduce costs. This growth has created powerful contract manufacturers (CMs) in several industries. Achieving a competitive cost position is often a primary motive for outsourcing. Outsourcing influences both the original equipment manufacturer's (OEM) and the CM's production levels, and, therefore, through learning‐by‐doing renders future costs dependent on past outsourcing decisions. As such, outsourcing should not be viewed as a static decision that, once made, is not revisited. We address these considerations by analyzing a two‐period game between an OEM and a powerful CM wherein both firms can reduce their production costs through learning‐by‐doing. We find that partial outsourcing, wherein the OEM simultaneously outsources and produces in‐house, can be an optimal strategy. Also, we find that the OEM's outsourcing strategy may be dynamic—i.e., change from period to period. In addition, we find both that the OEM may engage in production for leverage (i.e., produce internally when at a cost disadvantage) and that the CM may engage in low balling. These and other findings in this paper demonstrate the importance of considering learning, the power of the CM, and future periods when making outsourcing decisions.  相似文献   
385.
在中国,越来越多城市居民喜欢利用周末及节假日前往乡村地区休闲度假,给旅游地理学和休闲地理学研究带来了新的研究方向,为研究中国新型的甚至是未知的城乡关系提供了新的视角。这种新的休闲度假趋势主要产生于大中型城市周边的乡村地区。以位于长江三角洲的上海周边郊区为例,研究新型乡村旅游在城郊地区的发展,在保留和修缮传统乡村景观的同时,也产生出新型景观。旅游的发展促使乡村地区结构重组,建立了乡村旅游从业者的经营活动与当地农业发展之间的新联系。从中区分出两种乡村旅游经营模式:一种是为了适应当地乡村现代化发展需要并在当地政府支持下发展起来的乡村旅游示范村;另一种则是由个人开发且相对独立的小型农家乐或乡村旅游景点。这些地区乡村旅游的快速发展既有利于当地发展支柱产业,调整产业结构,扩大经济活动范围,也为城市居民重新审视乡村世界提供新视角。  相似文献   
386.
We consider the specific transformation of a Wiener process {X(t), t ≥ 0} in the presence of an absorbing barrier a that results when this process is “time-locked” with respect to its first passage time T a through a criterion level a, and the evolution of X(t) is considered backwards (retrospectively) from T a . Formally, we study the random variables defined by Y(t) ≡ X(T a  ? t) and derive explicit results for their density and mean, and also for their asymptotic forms. We discuss how our results can aid interpretations of time series “response-locked” to their times of crossing a criterion level.  相似文献   
387.
Nonlinear regression models arise when definite information is available about the form of the relationship between the response and predictor variables. Such information might involve direct knowledge of the actual form of the true model or might be represented by a set of differential equations that the model must satisfy. We develop M-procedures for estimating parameters and testing hypotheses of interest about these parameters in nonlinear regression models for repeated measurement data. Under regularity conditions, the asymptotic properties of the M-procedures are presented, including the uniform linearity, normality and consistency. The computation of the M-estimators of the model parameters is performed with iterative procedures, similar to Newton–Raphson and Fisher's scoring methods. The methodology is illustrated by using a multivariate logistic regression model with real data, along with a simulation study.  相似文献   
388.
This article examines a test procedure for checking the constancy of serial dependence via copulas for Markov time series data. It also provides a copula-based modeling approach for the dynamic serial dependence. Various parametric families of copulas offering different dependent structures are investigated. A score test is proposed for checking the constancy of a copula parameter. The score test is constructed and its asymptotic null distribution established under a two-stage estimation procedure. The test does not require specification of the probability distribution for the copula parameter. To capture the dynamics of dependence structure over time, autoregressive moving average and exponential type models are proposed. Illustrations are given based on simulated data and historic coffee prices data.  相似文献   
389.
The concept of inclusion probability proportional to size sampling plans excluding adjacent units separated by at most a distance of m (≥ 1) units {IPPSEA plans} is introduced. IPPSEA plans ensure that the first-order inclusion probabilities of units are proportional to size measures of the units, while the second-order inclusion probabilities are zero for pairs of adjacent units separated by a distance of m units or less. IPPSEA plans have been obtained by making use of binary, proper, and unequireplicated block designs and linear programing approach. The performance of IPPSEA plans using Horvitz–Thompson estimator of population total has been compared with existing sampling plans such as simple random sampling without replacement (SRSWOR), balanced sampling plans excluding adjacent units {BSA (m) plans}, probability proportional to size with replacement, Hartley and Rao's plan (1962 Hartley , H. O. , Rao , J. N. K. ( 1962 ). Sampling with unequal probabilities and without replacement . Ann. Math. Statist. 33 : 350374 .[Crossref] [Google Scholar]), Rao et al.'s strategy (1962 Rao , J. N. K. , Hartley , H. O. , Cochran , W. G. ( 1962 ). On a simple procedure of unequal probability sampling without replacement . J. Roy. Statist. Soc. B 24 : 482491 . [Google Scholar]), and Sampford's IPPS plan (1967 Sampford , M. R. ( 1967 ). On sampling without replacement with unequal probabilities of selection . Biometrika 54 ( 3 ): 499513 .[Crossref], [PubMed] [Google Scholar]) using a real life population. Unbiased estimation of Horvitz–Thompson estimator of population total is not possible in these types of plans because some of the second-order inclusion probabilities are zero. To resolve this problem, one approximate variance estimation technique has been suggested.  相似文献   
390.
In this article, we consider the product-limit quantile estimator of an unknown quantile function under a censored dependent model. This is a parallel problem to the estimation of the unknown distribution function by the product-limit estimator under the same model. Simultaneous strong Gaussian approximations of the product-limit process and product-limit quantile process are constructed with rate O[(log n)] for some λ > 0. The strong Gaussian approximation of the product-limit process is then applied to derive the laws of the iterated logarithm for product-limit process.  相似文献   
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