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271.
The interval estimate of the percentage of food received from the Food Bank with reference to household necessity is the main purpose of this article. A group of families having difficulty in purchasing enough food and thus receiving it from a charitable organization near Milan was considered. The group of families was divided into two groups depending on whether the householder was Italian or a foreigner. For the interval estimate of the ratio in question to be provided, we use the confidence intervals proposed by Galeone (2007) and Galeone and Pollastri (2012) but, in order to consider that the sample is stratified, it is necessary to introduce new methodologies. In fact, if a stratified sample is used, the properties of the estimator can be improved with respect to the estimator obtained from a simple random sample. In order to take into account the uncertainty of the estimate due to sampling, this paper proposes a new technique for the construction of confidence intervals of the indicator under examination based on the distribution of the ratio of two correlated Normal random variables when the sample is stratified. Using simulations, the confidence intervals for the ratio were compared when using the simple random sample with the confidence intervals based on a stratified sample. As a result, by using the stratified sample, the confidence intervals for the ratio can be improved because the width results reduced. Therefore, a combined ratio estimator was used in order to evaluate whether the help provided to the families satisfies their needs.  相似文献   
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This paper applies the semi-parametric Cox regression approach to model unemployment duration in Slovenia. The empirical analysis is based on a comprehensive dataset that consists of all unemployment spells in Slovenia from 2002 to 2005. The impact of the variables age, gender, level of education, and region on the hazard ratio is discussed. It takes longer for female and older unemployed persons to find a job and on average the duration of unemployment decreases with increasing level of education. Surprisingly, unemployed persons with a professional college degree or a bachelor’s degree are better off than unemployed persons with a master’s degree. A comparison of the Cox proportional hazards model and the Cox regression model with a time-dependent covariate reveals that the more appropriate model with a time-dependent covariate places greater emphasis on higher levels of education.
Alenka Kavkler (Corresponding author)Email:
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The paper presents the development of a cutting tool guide, specifically for the harvest of bamboo. The development was made based on precepts of eco-design and ergonomics, for prioritizing the physical health of the operator and the maintenance of the environment, as well as meet specific requirements of bamboo. The main goal is to spread the use of bamboo as construction material, handicrafts, among others, from a handy, easy assembly and material available tool.  相似文献   
278.
Looking back on the many prophets who tried to predict the future as if it were predetermined, at first sight any forward-looking activity is reminiscent of making predictions with a crystal ball. In contrast to fortune tellers, today??s exercises do not predict, but try to show different paths that an open future could take. A key motivation to undertake forward-looking activities is broadening the information basis for decision-makers to help them actively shape the future in a desired way. Experts, laypeople, or stakeholders may have different sets of values and priorities with regard to pending decisions on any issue related to the future. Therefore, considering and incorporating their views can, in the best case scenario, lead to more robust decisions and strategies. However, transferring this plurality into a form that decision-makers can consider is a challenge in terms of both design and facilitation of participatory processes. In this paper, we will introduce and critically assess a new qualitative method for forward-looking activities, namely CIVISTI (Citizen Visions on Science, Technology and Innovation; www.civisti.org), which was developed during an EU project of the same name. Focussing strongly on participation, with clear roles for citizens and experts, the method combines expert, stakeholder and lay knowledge to elaborate recommendations for decision-making in issues related to today??s and tomorrow??s science, technology and innovation. Consisting of three steps, the process starts with citizens?? visions of a future 30?C40?years from now. Experts then translate these visions into practical recommendations which the same citizens then validate and prioritise to produce a final product. The following paper will highlight the added value as well as limits of the CIVISTI method and will illustrate potential for the improvement of future processes.  相似文献   
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This article analyzes international commodity price movements, assesses food policies in response to price fluctuations, and explores the food security implications of price volatility on low-income groups. It focuses specifically on measurements, causes, and consequences of recent food price trends, variability around those trends, and price spikes. Combining these three components of price dynamics shows that the variation in real prices post-2000 was substantially greater than that in the 1980s and 1990s, and was approximately equal to the extreme volatility in commodity prices that was experienced in the 1970s. Macro policy, exchange rates, and petroleum prices were important determinants of price variability over 2005–2010, highlighting the new linkages between the agriculture-energy and agriculture-finance markets that affect the world food economy today. These linkages contributed in large part to misguided expectations and uncertainty that drove prices to their peak in 2008. The article also argues that there is a long-lasting effect of price spikes on food policy around the world, often resulting in self-sufficiency policies that create even more volatility in international markets. The efforts by governments to stabilize prices frequently contribute to even greater food insecurity among poor households, most of which are in rural areas and survive on the margin of net consumption and net production. Events of 2008—and more recently in 2010—underscore the impact of price variability for food security and the need for refocused policy approaches to prevent and mitigate price spikes.  相似文献   
280.
Although the empirical links between marriage and desistance are well established, very little is known about the degree to which cohabitation is associated with changes in criminal behavior. This is a significant oversight given that, among some segments of the population, cohabitation has become more common than marriage. In this article, the author investigated the links between cohabitation and desistance from crime. In doing so, particular attention was paid to the possibility that similarities between the apparent effects of marriage and cohabitation are obscured by variations in relationship quality and the increasing tendency for cohabitation to precede marriage. Analyses based on the National Longitudinal Survey of Youth 1997 (N = 3,232) indicate that cohabitation is associated with reductions in the rate of property and drug offending, but not the termination of violent, property, or drug offending. By contrast, marriage is consistently associated with large reductions in the rate of offending across the 3 crime categories as well as the abandonment of those crimes. These results provide greater insight into the links between adult family relationships, such as cohabitation and marriage, and desistance from crime.  相似文献   
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