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51.
幸福感是人们对主观生活质量进行的一种情感性评价,是满意感、快乐感和价值感的有机统一。本文在文献评述及概念界定的基础上,结合《中国综合社会调查(CGSS)》(2008年)提供的数据,从自我期望体验、身心健康体验、心态平衡体验等三个层次上深入分析我国城乡居民幸福感之间存在的差异。通过对分类变量进行有序逻辑斯蒂回归,发现城乡居民幸福感差异与以往的研究结论不同,即农村居民幸福感不高于城镇居民。同时,简要分析这种现象产生的原因并提出相关的对策建议。  相似文献   
52.
将新制度经济学关于制度与时间进程的分析方法,引入对"赌权开放"后的澳门博彩业对于澳门经济活动影响的考察,具有特殊意义。通过讨论博彩制度与财富增长之间的关系,可以看到,澳门博彩业在打破垄断引入竞争后,目前澳门博彩业带来的"经济神话"必然会破灭,因此关键仍然是需要加强"法治",将这一产业纳入法律监管的轨道。  相似文献   
53.
伴随限房、限贷、房产税等政策出台,我国商品房市场价格一直涨跌不明。商品房降价补差广告引起不少争议:购房者认为这是商家的承诺,在房屋降价时应当兑现;房产商仅将其视作宣传手段,不承担任何责任。降价补差广告的特殊性决定需要借助理性人客观评价标准分析法律属性。文章建议,在限制降价补差广告的基础上,将其定性为要约列入买卖合同,并明确其与欺诈性广告的区别,以保护消费者的信赖利益以及合理预期,促进商品房市场良性发展。  相似文献   
54.
In this paper, we introduce the concept of the p-mean almost periodicity for stochastic processes in non linear expectation spaces. The existence and uniqueness of square-mean almost periodic solutions to some non linear stochastic differential equations driven by G-Brownian motion are established under some assumptions for the coefficients. The asymptotic stability of the unique square-mean almost periodic solution in the square-mean sense is also discussed.  相似文献   
55.
We obtain the necessary and sufficient conditions so that any real function (x) is the conditional expectation E(h(X)/Xx) of a random variable X with continuous distribution function, where h is a given real, continuous and strictly monotonic function.  相似文献   
56.
In this article maximum likelihood techniques for estimating consumer demand functions when budget constraints are piecewise linear are exposited and surveyed. Consumer demand functions are formally derived under such constraints, and it is shown that the functions are themselves nonlinear as a result. The econometric problems in estimating such functions are exposited, and the importance of the stochastic specification is stressed, in particular the specification of both unobserved heterogeneity of preferences and measurement error. Econometric issues in estimation and testing are discussed, and the results of the studies that have been conducted to date are surveyed.  相似文献   
57.
ABSTRACT

This article considers linear social interaction models under incomplete information that allow for missing outcome data due to sample selection. For model estimation, assuming that each individual forms his/her belief about the other members’ outcomes based on rational expectations, we propose a two-step series nonlinear least squares estimator. Both the consistency and asymptotic normality of the estimator are established. As an empirical illustration, we apply the proposed model and method to National Longitudinal Study of Adolescent Health (Add Health) data to examine the impacts of friendship interactions on adolescents’ academic achievements. We provide empirical evidence that the interaction effects are important determinants of grade point average and that controlling for sample selection bias has certain impacts on the estimation results. Supplementary materials for this article are available online.  相似文献   
58.
For Canada's boreal forest region, the accurate modelling of the timing of the appearance of aspen leaves is important to forest fire management, as it signifies the end of the spring fire season that occurs after snowmelt. This article compares two methods, a midpoint rule and a conditional expectation method used to estimate the true flush date for interval-censored data from a large set of fire-weather stations in Alberta, Canada. The conditional expectation method uses the interval censored kernel density estimator of Braun et al. (2005 Braun , J. , Duchesne , T. , Stafford , J. E. ( 2005 ). Local likelihood density estimation for interval censored data . Canadian Journal of Statistics 33 : 3960 .[Crossref], [Web of Science ®] [Google Scholar]). The methods are compared via simulation, where true flush dates were generated from a normal distribution and then converted into intervals by adding and subtracting exponential random variables. The simulation parameters were estimated from the data set and several scenarios were considered. The study reveals that the conditional expectation method is never worse than the midpoint method, and that there is a significant advantage to this method when the intervals are large. An illustration of the methodology applied to the Alberta data set is also provided.  相似文献   
59.
We establish the upper nonpositive and all the lower bounds on the expectations of generalized order statistics based on a given distribution function with the finite mean and central absolute moment of a fixed order. We also describe the distributions for which the bounds are attained. The methods of deriving the lower nonpositive (upper nonnegative) and lower nonnegative (upper nonpositive) bounds are totally different. The first one, the greatest convex minorant method is the combination of the Moriguti and well-known Hölder inequalities and the latter one is based on the maximization of some norm on the properly chosen convex set. The paper completes the results of Cramer et al. [Evaluations of expected generalized order statistics in various scale units. Appl Math. 2002;29:285–295].  相似文献   
60.
Nonlinear mixed-effects (NLME) models are flexible enough to handle repeated-measures data from various disciplines. In this article, we propose both maximum-likelihood and restricted maximum-likelihood estimations of NLME models using first-order conditional expansion (FOCE) and the expectation–maximization (EM) algorithm. The FOCE-EM algorithm implemented in the ForStat procedure SNLME is compared with the Lindstrom and Bates (LB) algorithm implemented in both the SAS macro NLINMIX and the S-Plus/R function nlme in terms of computational efficiency and statistical properties. Two realworld data sets an orange tree data set and a Chinese fir (Cunninghamia lanceolata) data set, and a simulated data set were used for evaluation. FOCE-EM converged for all mixed models derived from the base model in the two realworld cases, while LB did not, especially for the models in which random effects are simultaneously considered in several parameters to account for between-subject variation. However, both algorithms had identical estimated parameters and fit statistics for the converged models. We therefore recommend using FOCE-EM in NLME models, particularly when convergence is a concern in model selection.  相似文献   
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