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1.
A major focus of India's ongoing policy debate over labour market flexibilization has been the statutory requirement that firms employing 100 or more workers cannot dismiss employees without prior government permission. The case for repealing that requirement (or greatly increasing the workforce threshold) is notably underpinned by Basu, Fields and Debgupta (2009). Here, the author challenges their particular theoretical argument for hiring and firing at will based on the voluntary signing of contracts, demonstrating that their general policy conclusion is logically unsustainable even within the framework of that model. The case for labour market flexibilization through voluntary contracting thus remains unfounded.  相似文献   
2.
We present the collaborative development of a web-based data collection and monitoring plan for thirty-two county councils within New Mexico's health council system. The monitoring plan, a key component in our multiyear participatory statewide evaluation process, was co-developed with the end users: representatives of the health councils. Guided by the Institute of Medicine's Community, Health Improvement Process framework, we first developed a logic model that delineated processes and intermediate systems-level outcomes in council development, planning, and community action. Through the online system, health councils reported data on intermediate outcomes, including policy changes and funds leveraged. The system captured data that were common across the health council system, yet was also flexible so that councils could report their unique accomplishments at the county level. A main benefit of the online system was that it provided the ability to assess intermediate, outcomes across the health council system. Developing the system was not without challenges, including creating processes to ensure participation across a large rural state; creating shared understanding of intermediate outcomes and indicators; and overcoming technological issues. Even through the challenges, however, the benefits of committing to using participatory processes far outweighed the challenges.  相似文献   
3.
A simple summary of a treatment effect is attractive, which is part of the explanation of the success of the Cox model when analysing time‐to‐event data since the relative risk measure is such a convenient summary measure. In practice, however, the Cox model may fail to give a reasonable fit, very often because of time‐changing treatment effect. The Aalen additive hazards model may be a good alternative as time‐changing effects are easily modelled within this model, but results are then evidently more complicated to communicate. In such situations, the odds of concordance measure (OC) is a convenient way of communicating results, and recently Martinussen & Pipper (2012) showed how a variant of the OC measure may be estimated based on the Aalen additive hazards model. In this study, we propose an estimator that should be preferred in observational studies as it always estimates the causal effect on the chosen scale, only assuming that there are no un‐measured confounders. The resulting estimator is shown to be consistent and asymptotically normal, and an estimator of its limiting variance is provided. Two real applications are provided.  相似文献   
4.
We derive two types of Akaike information criterion (AIC)‐like model‐selection formulae for the semiparametric pseudo‐maximum likelihood procedure. We first adapt the arguments leading to the original AIC formula, related to empirical estimation of a certain Kullback–Leibler information distance. This gives a significantly different formula compared with the AIC, which we name the copula information criterion. However, we show that such a model‐selection procedure cannot exist for copula models with densities that grow very fast near the edge of the unit cube. This problem affects most popular copula models. We then derive what we call the cross‐validation copula information criterion, which exists under weak conditions and is a first‐order approximation to exact cross validation. This formula is very similar to the standard AIC formula but has slightly different motivation. A brief illustration with real data is given.  相似文献   
5.
In this paper, we develop a semiparametric regression model for longitudinal skewed data. In the new model, we allow the transformation function and the baseline function to be unknown. The proposed model can provide a much broader class of models than the existing additive and multiplicative models. Our estimators for regression parameters, transformation function and baseline function are asymptotically normal. Particularly, the estimator for the transformation function converges to its true value at the rate n ? 1 ∕ 2, the convergence rate that one could expect for a parametric model. In simulation studies, we demonstrate that the proposed semiparametric method is robust with little loss of efficiency. Finally, we apply the new method to a study on longitudinal health care costs.  相似文献   
6.
在聚类问题中,若变量之间存在相关性,传统的应对方法主要是考虑采用马氏距离、主成分聚类等方法,但其可操作性或可解释性较差,因此提出一类基于模型的聚类方法,先对变量间的相关性结构建模(作为辅助信息)再做聚类分析。这种方法的优点主要在于:适用范围更宽泛,不仅能处理(线性)相关问题,而且还可以处理变量间存在的其他复杂结构生成的数据聚类问题;各个变量的重要性也可以通过模型的回归系数来体现;比马氏距离更稳健、更具操作性,比主成分聚类更容易得到解释,算法上也更为简洁有效。  相似文献   
7.
基于2006-2011年中国省级区域面板数据,应用时空加权回归模型(GTWR)实证考察了各驱动因素对碳排放规模和碳排放强度影响的时空差异。研究结果表明:大部分解释变量的时空系数估计值显著,波动性较为稳定,符号与预期一致,各驱动因素及其外溢效应在不同区域存在较强的空间异质性,且表现出一定的空间梯度分布。若实现区域差异化碳减排,需要充分考虑空间异质性和外溢性。  相似文献   
8.
选取华东六省一市作为研究对象,运用因子分析方法研究2012年该7个省市金融发展情况及其差异,并对其金融发展相似性进行聚类分析。在此基础上,采用1990—2012年数据,对聚类后的三类地区通过基于VAR模型的协整关系检验、Granger因果关系检验等建立变量间长期均衡模型,实证研究货币政策在华东地区不同省市效应的差异性。研究结果表明:三类地区经济增长和货币政策对于区域金融发展均具有明显的区域效应,经济发展和广义货币供应量与金融发展均呈正相关关系。鉴此,提出如下政策建议:正视区域经济发展差异,实施差别化货币调控政策;优化各区域金融结构差异,改善货币政策传导效应等。  相似文献   
9.
针对现有文献研究碳排放时忽略经济空间溢出效用以及对外贸易—碳排放非线性关系的缺憾,估算了2001-2011年中国29个省区碳排放量,然后构建半参数空间滞后模型,并结合工具变量法以解决对外贸易的内生性问题,实证研究了对外贸易对中国区域碳排放的影响。研究发现:(1)十年来中国贸易开放对碳排放的影响从促进逐渐开始转变为抑制。东部地区对外贸易发展较快,目前正处于逐渐抑制碳排放阶段;中部地区对外贸易水平较低,对外贸易的发展仍促进了碳排放的增加;西部地区对外贸易与碳排放的关系不明确。(2)半参数面板空间滞后模型比参数模型具有更高的拟合优度和更丰富的结论,它能够有效刻画碳经济现象中空间相关性与非线性特征。  相似文献   
10.
为明确企业统计数据质量的影响因素,定量描述各因素之间的关系,利用SEM模型,通过SPSS AMOS18.0软件进行数据分析,得到企业的信息化程度、企业重视化程度、企业统计力量、统计人员知识水平、统计人员地位、组织正规化程度6个因素的企业统计数据质量结构模型,并比较各个因素对企业统计数据质量影响的大小及各影响因素之间的相关关系,为进一步提高企业的统计数据工作提供了依据。  相似文献   
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