全文获取类型
收费全文 | 1124篇 |
免费 | 39篇 |
专业分类
管理学 | 84篇 |
民族学 | 6篇 |
人才学 | 2篇 |
人口学 | 105篇 |
丛书文集 | 12篇 |
理论方法论 | 190篇 |
综合类 | 9篇 |
社会学 | 626篇 |
统计学 | 129篇 |
出版年
2023年 | 13篇 |
2021年 | 6篇 |
2020年 | 17篇 |
2019年 | 26篇 |
2018年 | 22篇 |
2017年 | 37篇 |
2016年 | 34篇 |
2015年 | 24篇 |
2014年 | 32篇 |
2013年 | 209篇 |
2012年 | 47篇 |
2011年 | 39篇 |
2010年 | 32篇 |
2009年 | 35篇 |
2008年 | 39篇 |
2007年 | 45篇 |
2006年 | 38篇 |
2005年 | 37篇 |
2004年 | 40篇 |
2003年 | 30篇 |
2002年 | 23篇 |
2001年 | 22篇 |
2000年 | 18篇 |
1999年 | 22篇 |
1998年 | 16篇 |
1997年 | 12篇 |
1996年 | 14篇 |
1995年 | 16篇 |
1994年 | 18篇 |
1993年 | 16篇 |
1992年 | 10篇 |
1991年 | 11篇 |
1990年 | 8篇 |
1989年 | 7篇 |
1988年 | 9篇 |
1987年 | 9篇 |
1986年 | 6篇 |
1985年 | 12篇 |
1984年 | 8篇 |
1983年 | 9篇 |
1982年 | 11篇 |
1981年 | 15篇 |
1980年 | 7篇 |
1979年 | 11篇 |
1977年 | 9篇 |
1976年 | 7篇 |
1975年 | 4篇 |
1974年 | 8篇 |
1971年 | 3篇 |
1967年 | 4篇 |
排序方式: 共有1163条查询结果,搜索用时 15 毫秒
1.
2.
Diane Hope Weixing Zhu Corinna Gries Jacob Oleson Jason Kaye Nancy B. Grimm Lawrence A. Baker 《Urban Ecosystems》2005,8(3-4):251-273
We explored variations in inorganic soil nitrogen (N) concentrations across metropolitan Phoenix, Arizona, and the surrounding
desert using a probability-based synoptic survey. Data were examined using spatial statistics on the entire region, as well
as for the desert and urban sites separately. Concentrations of both NO3-N and NH4-N were markedly higher and more heterogeneous amongst urban compared to desert soils. Regional variation in soil NO3-N concentration was best explained by latitude, land use history, population density, along with percent cover of impervious
surfaces and lawn, whereas soil NH4-N concentrations were related to only latitude and population density. Within the urban area, patterns in both soil NO3-N and NH4-N were best predicted by elevation, population density and type of irrigation in the surrounding neighborhood. Spatial autocorrelation
of soil NO3-N concentrations explained 49% of variation among desert sites but was absent between urban sites. We suggest that inorganic
soil N concentrations are controlled by a number of ‘local’ or ‘neighborhood’ human-related drivers in the city, rather than
factors related to an urban-rural gradient. 相似文献
3.
There is an emerging consensus in empirical finance that realized volatility series typically display long range dependence with a memory parameter (d) around 0.4 (Andersen et al., 2001; Martens et al., 2004). The present article provides some illustrative analysis of how long memory may arise from the accumulative process underlying realized volatility. The article also uses results in Lieberman and Phillips (2004, 2005) to refine statistical inference about d by higher order theory. Standard asymptotic theory has an O(n-1/2) error rate for error rejection probabilities, and the theory used here refines the approximation to an error rate of o(n-1/2). The new formula is independent of unknown parameters, is simple to calculate and user-friendly. The method is applied to test whether the reported long memory parameter estimates of Andersen et al. (2001) and Martens et al. (2004) differ significantly from the lower boundary (d = 0.5) of nonstationary long memory, and generally confirms earlier findings. 相似文献
4.
文章剖析了英美物权法上“使用权”的概念 ,并解释了财产权就像“权利集束”这个常用比喻 ,并对美国普通法上财产法中的有关相邻方之间土地纠纷的法规进行了比较分析 ,其中特别比较了普通法上的私人妨害原则和中国物权法草案第 9章所规定的相邻权的概念 ,并将普通法体系中的各种私人土地使用协议和地役权与中国物权法草案第 16章的内容进行了对比。 相似文献
5.
In this article, the authors present a case example of a Chinese American lesbian woman who seeks counseling for career decision making. The client's career issues stem from cultural issues that have created a dichotomy in her life. Using an ecological model, the authors dissect the case, propose interventions, and identify potential problems that may arise. 相似文献
6.
Allan F. Abrahamse Peter A. Morrison Nancy Minter Bolton 《Population research and policy review》1994,13(4):383-398
Surname analysis is a potentially useful technique for identifying members of particular racial, ethnic, or language communities within a population. We review the existing state of the art for identifying persons of Hispanic or Asian origin, based on surnames distinctive of each group. We describe the logic of surname analysis, profile several available surname dictionaries, and illustrate their applications in local redistricting. Results of our ongoing validation studies suggest promising future directions for improving accuracy and broadening applications.This article is based on a paper presented at the annual Population Association of America meetings at Cincinnati, 1 April 1993. 相似文献
7.
Alan Phillips Alan Ebbutt Lesley France David Morgan Mick Ireson Lesley Struthers Guenter Heimann 《Pharmaceutical statistics》2003,2(4):241-251
The International Conference on Harmonisation guideline ‘Statistical Principles for Clinical Trials’ was adopted by the Committee for Proprietary Medicinal Products (CPMP) in March 1998, and consequently is operational in Europe. Since then more detailed guidance on selected topics has been issued by the CPMP in the form of ‘Points to Consider’ documents. The intent of these was to give guidance particularly to non‐statistical reviewers within regulatory authorities, although of course they also provide a good source of information for pharmaceutical industry statisticians. In addition, the Food and Drug Administration has recently issued a draft guideline on data monitoring committees. In November 2002 a one‐day discussion forum was held in London by Statisticians in the Pharmaceutical Industry (PSI). The aim of the meeting was to discuss how statisticians were responding to some of the issues covered in these new guidelines, and to document consensus views where they existed. The forum was attended by industry, academic and regulatory statisticians. This paper outlines the questions raised, resulting discussions and consensus views reached. It is clear from the guidelines and discussions at the workshop that the statistical analysis strategy must be planned during the design phase of a clinical trial and carefully documented. Once the study is complete the analysis strategy should be thoughtfully executed and the findings reported. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
8.
Mark J. Miller Nancy P. Newell Thomas P. Springer Don Wells 《The Career development quarterly》1992,40(4):334-339
The Self-Directed Search was administered to 68 university seniors who were majoring in Chemistry/Chemical Engineering, Elementary Education, and Office Administration. Their resulting three-letter summary codes were compared with three-letter college major codes obtained from the College Majors Finder. A high degree of agreement between the two sets of codes was found for each of the three majors. Effective methods for matching people to jobs have held the interest and occupied much time for career counselors and vocational theorists since the inception of the trait-factor approach to career counseling. More recently, Holland (1985a) broadened and clarified matching procedures through the development of his typological theory of vocational choice. Just as personality types and occupational environments have been organized using Holland's framework to foster an understanding of occupational choice, Holland's theory can also be used to explain other types of choices, such as choice of a college major. 相似文献
9.
Intuitive Toxicology: Expert and Lay Judgments of Chemical Risks 总被引:2,自引:0,他引:2
Human beings have always been intuitive toxicologists, relying on their senses of sight, taste, and smell to detect harmful or unsafe food, water, and air. As we have come to recognize that our senses are not adequate to assess the dangers inherent in exposure to a chemical substance, we have created the sciences of toxicology and risk assessment to perform this function. Yet despite this great effort to overcome the limitations of intuitive toxicology, it has become evident that even our best scientific methods still depend heavily on extrapolations and judgments in order to infer human health risks from animal data. Many observers have acknowledged the inherent subjectivity in the assessment of chemical risks and have indicated a need to examine the subjective or intuitive elements of expert and lay risk judgments. We have begun such an examination by surveying members of the Society of Toxicology and the lay public about basic toxicological concepts, assumptions, and interpretations. Our results demonstrate large differences between toxicologists and laypeople, as well as differences between toxicologists working in industry, academia, and government. In addition, we find that toxicologists are sharply divided in their opinions about the ability to predict a chemical's effect on human health on the basis of animal studies. We argue that these results place the problems of risk communication in a new light. Although the survey identifies misconceptions that experts should clarify for the public, it also suggests that controversies over chemical risks may be fueled as much by limitations of the science of risk assessment and disagreements among experts as by public misconceptions. 相似文献
10.