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151.
从一桩未决诉讼案会计处理的分歧着手,在阐述和分析分歧各方争论过程和适用准则的基础上,提出完善《企业会计准则第13号—或有事项》中关于未决诉讼类或有事项的判断及规范和《企业会计准则第29号—资产负债表日后事项》中关于调整事项及非调整事项的定义及相关解释的建议。  相似文献   
152.
借助医疗质量安全监控系统构建医疗安全不良事件预警模式,在医疗安全不良事件信息收集的基础上,通过系统进行自动定量分析和典型案例定性分析,发布预警信息,从根源上减少医疗安全不良事件的发生,保障医疗质量安全.  相似文献   
153.
Summary.  In magazine advertisements for new drugs, it is common to see summary tables that compare the relative frequency of several side-effects for the drug and for a placebo, based on results from placebo-controlled clinical trials. The paper summarizes ways to conduct a global test of equality of the population proportions for the drug and the vector of population proportions for the placebo. For multivariate normal responses, the Hotelling T 2-test is a well-known method for testing equality of a vector of means for two independent samples. The tests in the paper are analogues of this test for vectors of binary responses. The likelihood ratio tests can be computationally intensive or have poor asymptotic performance. Simple quadratic forms comparing the two vectors provide alternative tests. Much better performance results from using a score-type version with a null-estimated covariance matrix than from the sample covariance matrix that applies with an ordinary Wald test. For either type of statistic, asymptotic inference is often inadequate, so we also present alternative, exact permutation tests. Follow-up inferences are also discussed, and our methods are applied to safety data from a phase II clinical trial.  相似文献   
154.
This study examined the association among personality traits, life events and life satisfaction, and the underlying pathways from personality traits to life satisfaction. A total of 1,961 adolescents were recruited from 21 secondary schools in Hong Kong. The adolescent version of the Chinese Personality Assessment Inventory (CPAI-A), the Chinese Adolescent Life Events Checklist (CALEC) and the Satisfaction With Life Scale (SWLS) were employed to assess their personality, life events and life satisfaction, respectively. Multiple regression analysis showed there was an additional value of the indigenously derived scales of CPAI-A, including the Family Orientation, Harmony and Ren-Qing scales, in predicting life satisfaction beyond the universal personality traits. Results also indicated that there was a partial mediation effect of negative life events on personality traits in the prediction of life satisfaction.  相似文献   
155.
马戛尔尼觐见乾隆皇帝的礼仪照会怎样译出、由谁译出的问题在学界虽有论者提及,但并无定论。梳理使团成员日记、著作等原始资料以及相应汉译文可知,论者对礼仪照会的翻译问题莫衷一是与汉语译本中的误译不无关系。以英文资料为基础,比较使团成员对礼仪照会翻译的叙述能还原史实真相,能一窥当时特殊历史背景下翻译活动的特征和形态。  相似文献   
156.
Using a large panel dataset, this article investigates the degree of, and explanatory factors for, income mobility amongst the elderly in Sweden during the 1990s. It contributes to literature on welfare indicators for the older population as it supplements the welfare picture of the income adequacy with insights into income certainty during old age. Our methodological approach is to work with the administrative register data for Sweden, and this allows us to use a reliable record of incomes for a large sample of the elderly. Results for Sweden-born and foreign-born elderly persons are analysed separately and compared with corresponding groups of people of working age. Not surprisingly, nearly all of our results indicate that the income of the older population is more stable than that of the working age population, and upward income mobility is not as usual among the elderly as among other groups. The multivariate regression analyses identify several explanatory factors affecting those elderly who experienced income mobility. Most importantly, the death of a spouse increases the probability of downward income mobility, particularly amongst women. These and other findings of this research point to triggers of income poverty in old age that should be taken into account in policies concerned with the level and indexation of retirement income of future pensioners.  相似文献   
157.
The Constrained Extremal Distribution Selection Method   总被引:5,自引:0,他引:5  
Engineering design and policy formulation often involve the assessment of the likelihood of future events commonly expressed through a probability distribution. Determination of these distributions is based, when possible, on observational data. Unfortunately, these data are often incomplete, biased, and/or incorrect. These problems are exacerbated when policy formulation involves the risk of extreme events—situations of low likelihood and high consequences. Usually, observational data simply do not exist for such events. Therefore, determination of probabilities which characterize extreme events must utilize all available knowledge, be it subjective or observational, so as to most accurately reflect the likelihood of such events. Extending previous work on the statistics of extremes, the Constrained Extremal Distribution Selection Method is a methodology that assists in the selection of probability distributions that characterize the risk of extreme events using expert opinion to constrain the feasible values for parameters which explicitly define a distribution. An extremal distribution is then "fit" to observational data, conditional that the selection of parameters does not violate any constraints. Using a random search technique, genetic algorithms, parameters that minimize a measure of fit between a hypothesized distribution and observational data are estimated. The Constrained Extremal Distribution Selection Method is applied to a real world policy problem faced by the U.S. Environmental Protection Agency. Selected distributions characterize the likelihood of extreme, fatal hazardous material accidents in the United States. These distributions are used to characterize the risk of large scale accidents with numerous fatalities.  相似文献   
158.
The analysis of risk-return tradeoffs and their practical applications to portfolio analysis paved the way for Modern Portfolio Theory (MPT), which won Harry Markowitz a 1992 Nobel Prize in Economics. A typical approach in measuring a portfolio's expected return is based on the historical returns of the assets included in a portfolio. On the other hand, portfolio risk is usually measured using volatility, which is derived from the historical variance-covariance relationships among the portfolio assets. This article focuses on assessing portfolio risk, with emphasis on extreme risks. To date, volatility is a major measure of risk owing to its simplicity and validity for relatively small asset price fluctuations. Volatility is a justified measure for stable market performance, but it is weak in addressing portfolio risk under aberrant market fluctuations. Extreme market crashes such as that on October 19, 1987 ("Black Monday") and catastrophic events such as the terrorist attack of September 11, 2001 that led to a four-day suspension of trading on the New York Stock Exchange (NYSE) are a few examples where measuring risk via volatility can lead to inaccurate predictions. Thus, there is a need for a more robust metric of risk. By invoking the principles of the extreme-risk-analysis method through the partitioned multiobjective risk method (PMRM), this article contributes to the modeling of extreme risks in portfolio performance. A measure of an extreme portfolio risk, denoted by f(4), is defined as the conditional expectation for a lower-tail region of the distribution of the possible portfolio returns. This article presents a multiobjective problem formulation consisting of optimizing expected return and f(4), whose solution is determined using Evolver-a software that implements a genetic algorithm. Under business-as-usual market scenarios, the results of the proposed PMRM portfolio selection model are found to be compatible with those of the volatility-based model. However, under extremely unfavorable market conditions, results indicate that f(4) can be a more valid measure of risk than volatility.  相似文献   
159.
In this article, we formulate a semiparametric model for counting processes in which the effect of covariates is to transform the time scale for a baseline rate function. We assume an arbitrary dependence structure for the counting process and propose a class of estimating equations for the regression parameters. Asymptotic results for these estimators are derived. In addition, goodness of fit methods for assessing the adequacy of the accelerated rates model are proposed. The finite-sample behavior of the proposed methods is examined in simulation studies, and data from a chronic granulomatous disease study are used to illustrate the methodology.  相似文献   
160.
免赔额和NCD赔付条件下保险索赔次数的分布   总被引:5,自引:4,他引:5  
本文分析了免赔额及NCD赔付条件对索赔次数分布的影响,通过比较风险事件与索赔事件的差异引出了一类同质集合保单索赔次数的分布(PG分布);给出了PG分布的性质及参数估计方法。通过两个保险实例展示了数据拟合效果。  相似文献   
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