全文获取类型
收费全文 | 1323篇 |
免费 | 93篇 |
国内免费 | 12篇 |
专业分类
管理学 | 222篇 |
民族学 | 5篇 |
人口学 | 21篇 |
丛书文集 | 49篇 |
理论方法论 | 35篇 |
综合类 | 468篇 |
社会学 | 122篇 |
统计学 | 506篇 |
出版年
2023年 | 14篇 |
2022年 | 15篇 |
2021年 | 22篇 |
2020年 | 39篇 |
2019年 | 58篇 |
2018年 | 56篇 |
2017年 | 76篇 |
2016年 | 51篇 |
2015年 | 64篇 |
2014年 | 87篇 |
2013年 | 237篇 |
2012年 | 90篇 |
2011年 | 85篇 |
2010年 | 61篇 |
2009年 | 73篇 |
2008年 | 53篇 |
2007年 | 48篇 |
2006年 | 47篇 |
2005年 | 43篇 |
2004年 | 33篇 |
2003年 | 33篇 |
2002年 | 32篇 |
2001年 | 20篇 |
2000年 | 16篇 |
1999年 | 12篇 |
1998年 | 8篇 |
1997年 | 6篇 |
1996年 | 7篇 |
1995年 | 7篇 |
1994年 | 8篇 |
1993年 | 7篇 |
1992年 | 3篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1988年 | 4篇 |
1986年 | 1篇 |
1984年 | 1篇 |
1981年 | 2篇 |
1979年 | 2篇 |
1977年 | 2篇 |
排序方式: 共有1428条查询结果,搜索用时 15 毫秒
81.
景美霞 《山西大同大学学报(社会科学版)》2009,23(3):101-102,112
过程写作法近年来盛行海外,已经成为西方写作教学主流。它将写作视为交互循环的心理认知过程和语言交际过程,重视写作的具体过程及其交际性,被证明对于提高学习者写作能力效果显著。本文系统地研究了过程写作法产生的背景、理论基础及其在写作教学中的实际应用。 相似文献
82.
QMRA for Drinking Water: 2. The Effect of Pathogen Clustering in Single‐Hit Dose‐Response Models
下载免费PDF全文
![点击此处可从《Risk analysis》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Spatial and/or temporal clustering of pathogens will invalidate the commonly used assumption of Poisson‐distributed pathogen counts (doses) in quantitative microbial risk assessment. In this work, the theoretically predicted effect of spatial clustering in conventional “single‐hit” dose‐response models is investigated by employing the stuttering Poisson distribution, a very general family of count distributions that naturally models pathogen clustering and contains the Poisson and negative binomial distributions as special cases. The analysis is facilitated by formulating the dose‐response models in terms of probability generating functions. It is shown formally that the theoretical single‐hit risk obtained with a stuttering Poisson distribution is lower than that obtained with a Poisson distribution, assuming identical mean doses. A similar result holds for mixed Poisson distributions. Numerical examples indicate that the theoretical single‐hit risk is fairly insensitive to moderate clustering, though the effect tends to be more pronounced for low mean doses. Furthermore, using Jensen's inequality, an upper bound on risk is derived that tends to better approximate the exact theoretical single‐hit risk for highly overdispersed dose distributions. The bound holds with any dose distribution (characterized by its mean and zero inflation index) and any conditional dose‐response model that is concave in the dose variable. Its application is exemplified with published data from Norovirus feeding trials, for which some of the administered doses were prepared from an inoculum of aggregated viruses. The potential implications of clustering for dose‐response assessment as well as practical risk characterization are discussed. 相似文献
83.
Estimation of benchmark doses (BMDs) in quantitative risk assessment traditionally is based upon parametric dose‐response modeling. It is a well‐known concern, however, that if the chosen parametric model is uncertain and/or misspecified, inaccurate and possibly unsafe low‐dose inferences can result. We describe a nonparametric approach for estimating BMDs with quantal‐response data based on an isotonic regression method, and also study use of corresponding, nonparametric, bootstrap‐based confidence limits for the BMD. We explore the confidence limits’ small‐sample properties via a simulation study, and illustrate the calculations with an example from cancer risk assessment. It is seen that this nonparametric approach can provide a useful alternative for BMD estimation when faced with the problem of parametric model uncertainty. 相似文献
84.
This tutorial focuses on how to produce reliable and generalizable data from random‐digit‐dialing (RDD) landline and cell phone surveys. The article notes that RDD response rates have declined and explores the impact of this pronounced decline. The tutorial addresses order, response mode, and many other biases, sample size, cooperation and response rates, weighting, and hybrid designs‐all using examples from risk analysis to illustrate the key points. The article ends with a brief review of the advantages and disadvantages of major Internet and paper surveys tools, and how these can be molded and sometimes combined in repeated, longitudinal, and other designs to answer questions about risk preferences and perceptions. 相似文献
85.
Arijit Chaudhuri Tasos C. Christofides Amitava Saha 《Statistical Methods and Applications》2009,18(3):389-418
In estimating the proportion of people bearing a sensitive attribute A, say, in a given community, following Warner’s (J Am Stat Assoc 60:63–69, 1965) pioneering work, certain randomized response
(RR) techniques are available for application. These are intended to ensure efficient and unbiased estimation protecting a
respondent’s privacy when it touches a person’s socially stigmatizing feature like rash driving, tax evasion, induced abortion,
testing HIV positive, etc. Lanke (Int Stat Rev 44:197–203, 1976), Leysieffer and Warner (J Am Stat Assoc 71:649–656, 1976),
Anderson (Int Stat Rev 44:213–217, 1976, Scand J Stat 4:11–19, 1977) and Nayak (Commun Stat Theor Method 23:3303–3321, 1994)
among others have discussed how maintenance of efficiency is in conflict with protection of privacy. In their RR-related activities
the sample selection is traditionally by simple random sampling (SRS) with replacement (WR). In this paper, an extension of
an essential similarity in case of general unequal probability sample selection even without replacement is reported. Large
scale surveys overwhelmingly employ complex designs other than SRSWR. So extension of RR techniques to complex designs is
essential and hence this paper principally refers to them. New jeopardy measures to protect revelation of secrecy presented
here are needed as modifications of those in the literature covering SRSWR alone. Observing that multiple responses are feasible
in addressing such a dichotomous situation especially with Kuk’s (Biometrika 77:436–438, 1990) and Christofides’ (Metrika
57:195–200, 2003) RR devices, an average of the response-specific jeopardizing measures is proposed. This measure which is
device dependent, could be regarded as a technical characteristic of the device and it should be made known to the participants
before they agree to use the randomization device.
The views expressed are the authors’, not of the organizations they work for. Prof Chaudhuri’s research is partially supported
by CSIR Grant No. 21(0539)/02/EMR-II. 相似文献
86.
Lydia F. Killos PhD Linda C. Hancock FNP PhD Amanda Wattenmaker McGann MPH Adrienne E. Keller PhD 《Journal of American college health : J of ACH》2013,61(3):228-230
Abstract Objective: Social norms campaigns are a cost-effective way to reduce high-risk drinking on college campuses. This study compares effectiveness of a “standard” social norms media (SNM) campaign for those with and without exposure to additional educational sessions using audience response technology (“clickers”). Methods: American College Health Association's National College Health Assessment questions are used to evaluate actual and perceived use. Additional survey questions assess individual exposure to the interventions. Results: The authors find “clicker” technology to be more effective than social norms poster media alone in reducing misperceptions of normative alcohol use for those students who attended clicker sessions. Conclusion: Poster SNM campaigns may be most effective when supported by group “clicker” heath-related sessions. 相似文献
87.
《Journal of workplace behavioral health》2013,28(2):79-88
No abstract available for this article. 相似文献
88.
《统计学通讯:模拟与计算》2013,42(3):773-785
Summary The concepts of D-, A- and E-minimax optimality criteria of designs for estimating the slopes of a response surface are considered for situations where the region of interest may not be identical to the experimental region. Optimal second-order designs are derived for the situation where the experimental region and the region of interest are both hyperspherical with a common centre. The dependence of the optimal design on the relative sizes of the regions is investigated. Further, the perfomance of designs optimal for one region in estimating slopes in other regions is also examined. 相似文献
89.
《Journal of Statistical Computation and Simulation》2012,82(1-4):261-270
Sensitivity analysis of air scattered neutron dose at several distances from a particle accelerator with respect to shield thickness and neutron yield distributions has been carried out. We illustrate the successful use of Response Surface Methodology in studying the behaviour of the sensitivity coefficients for main effects and interaction terms. A comparison of the full six factor design and the orthogonal Central Composite Design has been made. The overhead shield is found to be the most sensitive parameter followed by the high energy part of the neutron energy distribution. 相似文献
90.