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11.
由于对受众的想象存在着文化低端化定势,当下都市娱乐类传媒大量采用了流行言语和时尚言说方式,形成一种夸张、油腻、生僻化、雷同的言说风格。这种言说风格通过持续而广泛的传播,正在影响着我们的语言规范,其更深的社会文化背景则是公众心态的普遍浮躁和对语言规范的解构。若不注意控制这种言语文风,将对语言体系的健康发展产生过多的噪音。  相似文献   
12.
上海第四制药厂在抗生素生产过程系统节能技术研究中对该厂的热能供应系统提出了3个改造方案.本文以该热力系统为例,通过对各方案的技术经济分析比较,以揭示热力系统经济评估的内在含义,并提出了用参数“净年收益”作为评估依据之一的建议.  相似文献   
13.
对一般线性模型中参数β的最小二乘估计和岭估计进行了修正;把岭估计中各分量的非均匀压缩修为均匀压缩,从而得到了β的一种均匀压缩估计^βa,并给出了具体的求法和适用范围  相似文献   
14.
LetX1,X2, ..., be real-valued random variables forming a strictly stationary sequence, and satisfying the basic requirement of being either pairwise positively quadrant dependent or pairwise negatively quadrant dependent. LetF^ be the marginal distribution function of theXips, which is estimated by the empirical distribution functionFn and also by a smooth kernel-type estimateFn, by means of the segmentX1, ...,Xn. These estimates are compared on the basis of their mean squared errors (MSE). The main results of this paper are the following. Under certain regularity conditions, the optimal bandwidth (in the MSE sense) is determined, and is found to be the same as that in the independent identically distributed case. It is also shown thatn MSE(Fn(t)) andnMSE (F^n(t)) tend to the same constant, asn→∞ so that one can not discriminate be tween the two estimates on the basis of the MSE. Next, ifi(n) = min {k∈{1, 2, ...}; MSE (Fk(t)) ≤ MSE (Fn(t))}, then it is proved thati(n)/n tends to 1, asn→∞. Thus, once again, one can not choose one estimate over the other in terms of their asymptotic relative efficiency. If, however, the squared bias ofF^n(t) tends to 0 sufficiently fast, or equivalently, the bandwidthhn satisfies the requirement thatnh3n→ 0, asn→∞, it is shown that, for a suitable choice of the kernel, (i(n) ?n)/(nhn) tends to a positive number, asn→∞ It follows that the deficiency ofFn(t) with respect toF^n(t),i(n) ?n, is substantial, and, actually, tends to ∞, asn→∞. In terms of deficiency, the smooth estimateF^n(t) is preferable to the empirical distribution functionFn(t)  相似文献   
15.
We develop four asymptotic interval estimators and one exact interval estimator for the odds ratio (OR) under stratified random sampling with matched pairs. We apply Monte Carlo simulation to evaluate the performance of these five interval estimators. We note that the conditional score test-based interval estimator with a monotonic transformation and the interval estimator based on the Mantel–Haenszel (MH) type point estimator with the logarithmic transformation are generally preferable to the others considered here. We also note that the conditional exact confidence interval can be of use when the total number of matched pairs with discordant responses is small.  相似文献   
16.
We describe a model to obtain strengths and rankings of players appearing in golf's Ryder Cup. Obtaining rankings is complicated because of two reasons. First, competitors do not compete on an equal number of occasions, with some competitors appearing too infrequently for their ranking to be estimated with any degree of certainty, and second, different competitors experience different levels of volatility in results. Our approach is to assume the competitor strengths are drawn from some common distribution. For small numbers of competitors, as is the case here, we fit the model using Monte-Carlo integration. Results suggest there is very little difference between the top performing players, though Scotland's Colin Montgomerie is estimated as the strongest Ryder Cup player.  相似文献   
17.
《Journal of Policy Modeling》2014,36(6):1048-1065
The stability of inflation differentials is an important condition for the smooth working of a currency area, such as the European Economic and Monetary Union. In the presence of stability, changes in national inflation rates, while holding Euro area inflation fixed contemporaneously, should be only transitory. If this is the case, the rate of inflation of the whole area can also be interpreted as a predictor, at least in the long-run, of the different national inflation rates. However, in this paper we show that this condition is satisfied only for a small number of countries, including France and Italy. Better convergence results for inflation differentials are, instead, found for the USA. Some policy implications are drawn for the Eurozone.  相似文献   
18.
In this paper, the reliability of a system is discussed when the strength of the system and the stress imposed on it are independent, non-identical exponentiated Pareto distributed random variables. Different point estimations and interval estimations are proposed. The point estimators obtained are maximum likelihood, uniformly minimum variance unbiased and Bayesian estimators. The interval estimations obtained are approximate, exact, bootstrap-p and bootstrap-t confidence intervals and Bayesian credible interval. Different methods and the corresponding confidence intervals are compared using Monte-carlo simulations.  相似文献   
19.
以不同生产资料所有制的经营性资产价值量作为衡量主次地位的边界标准,估算第一产业公有制与非公有制的资产规模及其比重变化,并在前人估算的基础上,延伸估算第二和第三产业两种所有制的资产规模及其比重变化。结果发现:截至2012年,中国三次产业经营性总资产约为487.53万亿元,其中公有制经济的资产规模是258.39万亿元,占53%;第二、三产业非公有制经济占增加值和就业规模的比重分别为67.59%和75.20%。这表明,公有制资产仍占主体,非公有制经济贡献占优,中国社会主义基本经济制度充满活力,从而为我国社会主义初级阶段的所有制改革和坚持“两个毫不动摇”的政策提供了理论依据。  相似文献   
20.
This paper presents an effective and efficient method for solving a special class of mixed integer fractional programming (FP) problems. We take a classical reformulation approach for continuous FP as a starting point and extend it for solving a more general class of mixed integer (0–1) fractional programming problems.To stress the practical relevance of the research we focus on a real-life application in paper production industry. The constantly advancing physical knowledge of large scale pulp and paper production did have a substantial impact on an existing DSS in which mixed integer (0–1) fractional programming is introduced. We show that the motivation to solve a real-life fractional programming problem can provide the basis for a new approach in a new context that has an added value of its own, even outside the given application area. We describe the main characteristics of the DSS, the necessity to develop a non-iterative solution procedure and demonstrate both the effectiveness and efficiency of the proposed approach from practical data sets.  相似文献   
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