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31.
从现在到2020年是打赢脱贫攻坚战的关键时期,从农民自身角度研究搬迁意愿,对加快实施易地扶贫移民搬迁具有重要意义。研究依据西方微观人口迁移理论:地方效用理论、计划行为理论和效价[CD*2]期望理论,整合构建了中国国情下由政府引导的易地扶贫搬迁意愿的理论分析框架。以陕南移民搬迁为例,在验证性因子分析的基础上,运用有序Logit模型和最优尺度模型对理论假设进行检验。结果显示:①心理因素、政策和预期因素、环境因素对搬迁意愿具有显著影响 ②控制变量中家庭人口数、非农劳动力比例、家庭成员求学婚姻等控制变量与搬迁意愿显著相关;③没有搬迁的主要的顾虑是搬迁后找不到工作、城镇生活成本高、搬迁成本高、搬迁后的适应等问题。研究建议政府部门在搬迁补助、就业安置、搬迁后适应等方面加大支持力度,增强搬迁的信心。  相似文献   
32.
基于主体不平等的跨国界河流水资源分配的破产博弈研究   总被引:1,自引:0,他引:1  
基于破产理论和讨价还价博弈,构建水资源分配的破产博弈模型。借鉴国际水法,构建主体在水资源分配谈判中的议价能力评价指标体系,将议价能力运用到破产博弈模型中,突出主体在水资源分配中的不平等性,减少水资源分配量与贡献、需求量和对水资源依赖程度的非对称性;结合主体的谈判破裂点,根据主体满意度函数的联动函数寻找水资源分配的最优解,使分配能同时满足个体理性和集体理性,并对澜沧江-湄公河流域进行实例研究。  相似文献   
33.
坚持和发展社会主义市场经济,必须紧紧抓住和解决好基本制度、生产目的和资源配置这三个根本问题.这三个根本问题也构成了中国特色社会主义政治经济学的核心内容.在基本制度方面,必须坚持公有制主体地位不能动摇,国有经济主导作用不能动摇;坚持按劳分配为主体、使改革发展成果更多更公平惠及全体人民.在生产目的上,要满足广大人民日益增长、不断升级和个性化的物质文化和生态环境需要.在解放和发展生产力的同时,保证被解放和发展了的生产力归人民所有,走可持续发展道路.在资源配置方面,社会主义国家由于有公有制经济的全力配合,政府对资源配置才能真正发挥“看得见的手”的作用,当然其效果如何还得看这只手有没有遵循经济发展的客观规律.中国特色社会主义追求的是共同富裕,公有制的存在和发展保证了经济发展成果由人民群众共享,从而中国特色社会主义的效率必然是也必须是最广大人民群众的效率,从而这个效率必然是与公平一致的.  相似文献   
34.
The Burr XII distribution offers a flexible alternative to the distributions that play important role for modelling data in reliability, risk and process capability. However, estimating the shape parameters of the Burr XII distribution is a challenging problem. The classical estimation methods such as maximum likelihood and least squares are often used to estimate the parameters of the Burr XII distribution, but these methods are very sensitive to the outliers in the data. Thus, a robust estimation method alternative to the classical methods is needed to find robust estimators that are less sensitive to the outliers in the data. The purpose of this paper is to use the optimal B-robust estimation method [Hampel FR, Ronchetti EM, Rousseeuw PJ, Stahel WA. Robust statistics: the approach based on influence functions. New York: Wiley; 1986] to obtain robust estimators for the shape parameters of the Burr XII distribution. The simulation results show that the optimal B-robust estimators generally outperform the classical estimators in terms of the bias and root mean square errors when there are outliers in data.  相似文献   
35.
Previous studies focus on homogeneous and isotropic assumptions about the noisy data. Many methods have been developed recently for fitting concentric circles to data. In this paper, these statistical assumptions have been relaxed. To the best of our knowledge, only one iterative method has been recently developed. Due to its complexity, no such algorithm is available to compute the reliable maximum likelihood estimator (MLE). Accordingly, we have developed four new methods that outperform the existing methods including the orthogonal distance regression (ODR). We also discuss which of these methods is superior according to the four principles: statistical efficiency, accuracy, robustness, and computational efficiency. Numerical experiments on synthetic and real images have been conducted to validate our findings.  相似文献   
36.
Reform of China's Household Registration system(HRS) has been entering a new stage and deserves us to research.The paper argues that reform of HRS should have multiple objectives.It examines various local efforts and practices of the reform and claims that the point system is one of the most feasible alternative systems for the HRS that can fit those multiple reform objectives.The system could also be treated as the new institutional basic for public welfare provision and rights allocation,and a new governance means for population issues as well in China's transitional period.  相似文献   
37.
In this paper, we consider the inventory decisions of two retailers who are supplied by a single supplier with uncertain capacity. When capacity is allocated in proportion to the retailers׳ orders, the retailers compete for the capacity by inflating their orders (i.e., the rationing game). In addition, we allow the retailers to implement transshipment between them such that they cooperate by transshipping the surplus stock of one to another who is out of stock. Our analysis of Nash equilibrium orders shows that, while order inflation in the equilibrium orders persists in the rationing game with transshipment, it may not occur if the amount of capacity shortage is small and the transshipment prices are low. Thus, carefully chosen transshipment prices may alleviate order inflation behavior. We also characterize centralized orders that maximize the total profit of the retailers and compare them to equilibrium orders. In particular, we investigate coordinating transshipment prices that induce the retailers to choose centralized orders. Our numerical analysis shows that, even for two identical retailers, coordinating transshipment prices exist in a more limited range of parameter values in the rationing game than they do outside the rationing game due to capacity uncertainty and limitation.  相似文献   
38.
Multivariate stochastic volatility models with skew distributions are proposed. Exploiting Cholesky stochastic volatility modeling, univariate stochastic volatility processes with leverage effect and generalized hyperbolic skew t-distributions are embedded to multivariate analysis with time-varying correlations. Bayesian modeling allows this approach to provide parsimonious skew structure and to easily scale up for high-dimensional problem. Analyses of daily stock returns are illustrated. Empirical results show that the time-varying correlations and the sparse skew structure contribute to improved prediction performance and Value-at-Risk forecasts.  相似文献   
39.
We propose tests for parameter constancy in the time series direction in panel data models. We construct a locally best invariant test based on Tanaka [Time series analysis: nonstationary and noninvertible distribution theory. New York: Wiley; 1996] and an asymptotically point optimal test based on Elliott and Müller [Efficient tests for general persistent time variation in regression coefficients. Rev Econ Stud. 2006;73:907–940]. We derive the limiting distributions of the test statistics as T→∞ while N is fixed, and calculate the critical values by applying numerical integration and response surface regression. Simulation results show that the proposed tests perform well if we apply them appropriately.  相似文献   
40.
This work investigates an optimal financing and dividend problem for an insurer whose surplus process is modulated by an observable continuous-time and finite-state Markov chain. We assume that the insurer should never go bankrupt by issuing new equity. The goal of the insurer is to maximize the expected present value of the dividends payout minus the discounted cost of equity issuance. We obtain the optimal policies and explicit expressions for the value functions when the risk reserve process is modeled by both upward jump model and its diffusion approximation. Numerical illustrations of the sensitivities of the model parameters are provided.  相似文献   
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