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We consider a generalization of the proportionate flow shop problem with the makespan objective. Each job has a processing requirement and each machine has a characteristic value. In our case, we assume that the time a job occupies a machine is equal to the processing requirement of the job plus a setup time that is equal to the characteristic value of that machine. In this paper, we consider permutation schedules and show that the problem is solvable in polynomial time when the number of machines is fixed.  相似文献   
124.
The performance of Anderson's classification statistic based on a post-stratified random sample is examined. It is assumed that the training sample is a random sample from a stratified population consisting of two strata with unknown stratum weights. The sample is first segregated into the two strata by post-stratification. The unknown parameters for each of the two populations are then estimated and used in the construction of the plug-in discriminant. Under this procedure, it is shown that additional estimation of the stratum weight will not seriously affect the performance of Anderson's classification statistic. Furthermore, our discriminant enjoys a much higher efficiency than the procedure based on an unclassified sample from a mixture of normals investigated by Ganesalingam and McLachlan (1978).  相似文献   
125.
All social groups live according to a variety of rules or social norms. In many societies, many of these norms govern female sexual behavior. This article explores the male voice and the potential governance of female sexuality in women's magazines. A ten-year textual analysis of two women's magazines targeted to different racial readerships revealed the strong presence of male authors in these magazines. Some of these male authors helped women to better understand men and build stronger relationships, but others attempted to govern the sexuality of women in a variety of ways. Her current projects explore gender, race, and sexuality in media.  相似文献   
126.
Y Tang 《人口研究》1989,(5):24-29
An important cause of resistance to China's family planning (FP) program in rural areas is the need to have children to support parents in their old age. Provision of insurance for old age support will facilitate the implementation of the FP program among the rural population. A trial project was initiated in five cities and counties in Fujian province i 1986. The program included schemes for both eligible couples and for single children. The township or the village pays a lump sum or monthly premium to the insurance company for each couple, which enables them to collect 30-35 Yuan/month after they reach 55 years of age. To further expand the insurance program, a survey was conducted in 1987 to determine whether rural farmers would be willing and able to pay the insurance premium themselves. 77% of the respondents reported that they could afford to pay 60% of the premium. Among them, 59% were willing to pay. It was suggested that besides individual purchase of the insurance plan, the rural communities could contribute to the payment of the premium from the fines for unplanned births, from the local tax, and from the country government budget. Preferential treatment should be given to the couples of two daughters who receives sterilization; the communities should pay for a larger share of their premium. The current insurance scheme needs to be reformed so that the plan can offer more than the individual's bank savings. To do so, the insurance company needs to be able to invest their premium income and obtain higher returns. The employees of the insurance company need to improve their work efficiency to win the trust of the people in the program.  相似文献   
127.
This note provides more results on moments and cumulants of the D compound Poisson distribution through the properties of the multivariate generalized power series distribution.  相似文献   
128.
Single-objective-based decision-tree analysis has been extensively and successfully used in numerous decision-making problems since its formal introduction by Howard Raiffa more than two decades ago. This paper extends the traditional methodology to incorporate multiple noncommensurate objective functions and use of the conditional expected value of the risk of extreme and catastrophic events. The proposed methodology considers the cases where (a) a finite number of actions are available at each decision node and (b) discrete or continuous states of nature can be presented at each chance node. The proposed extension of decision-tree analysis is introduced through an example problem that leads the reader step-by-step into the methodological procedure. The example problem builds on flood warning systems. Two noncommensurate objectives—the loss of lives and the loss of property (including monetary costs of the flood warning system)–are incorporated into the decision tree. In addition, two risk measures—the common expected value and the conditional expected value of extreme and catastrophic events—are quantified and are also incorporated into the decision-making process. Theoretical difficulties associated with the stage-wise calculation of conditional expected values are identified and certain simplifying assumptions are made for computational tractibility. In particular, it is revealed that decisions concerning experimentation have a very interesting impact on the noninferior solution set of options—a phenomenon that has no equivalence in the single-objective case.  相似文献   
129.
Two-stage procedures are introduced to control the width and coverage (validity) of confidence intervals for the estimation of the mean, the between groups variance component and certain ratios of the variance components in one-way random effects models. The procedures use the pilot sample data to estimate an “optimal” group size and then proceed to determine the number of groups by a stopping rule. Such sampling plans give rise to unbalanced data, which are consequently analyzed by the harmonic mean method. Several asymptotic results concerning the proposed procedures are given along with simulation results to assess their performance in moderate sample size situations. The proposed procedures were found to effectively control the width and probability of coverage of the resulting confidence intervals in all cases and were also found to be robust in the presence of missing observations. From a practical point of view, the procedures are illustrated using a real data set and it is shown that the resulting unbalanced designs tend to require smaller sample sizes than is needed in a corresponding balanced design where the group size is arbitrarily pre-specified.  相似文献   
130.
It is shown that the weak Pareto principle consists of two parts: Pareto Neutrality and Weak Pareto Unanimity. It is the Pareto Neutrality which is responsible for the Paradox of the Paretian Libertarian. The libertarianism condition can also be factorized into two parts: the Libertarian Invariance and the Libertarian Non-Imposition. It is the Libertarian Invariance which is responsible or the Paradox of the Paretian Libertarian. Under conditions of Unrestricted Domain, Pareto Neutrality and Libertarian Invariance, if we require a social preference to be acyclic, then(1) neither can individuals' personal rights be respected, nor can they be reversed;(2) neither can unanimous group rights be respected, nor can they be reversed. Consequently, the Paradox of the Paretian Libertarian is due to the inconsistent use of information contained in the weak Pareto principle and the libertarianism condition.I would like to thank Nick Baigent, Prasanta Pattanaik, John Riley, Amartya Sen and Kotaro Suzumura for their comments. I would also like to thank two anonymous referees for their suggestions and comments on earlier drafts of the paper which led to a great improvement of the present version.  相似文献   
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