全文获取类型
收费全文 | 1036篇 |
免费 | 38篇 |
国内免费 | 1篇 |
专业分类
管理学 | 206篇 |
民族学 | 5篇 |
人口学 | 82篇 |
丛书文集 | 8篇 |
理论方法论 | 116篇 |
综合类 | 11篇 |
社会学 | 512篇 |
统计学 | 135篇 |
出版年
2023年 | 9篇 |
2021年 | 5篇 |
2020年 | 24篇 |
2019年 | 20篇 |
2018年 | 19篇 |
2017年 | 31篇 |
2016年 | 23篇 |
2015年 | 18篇 |
2014年 | 31篇 |
2013年 | 262篇 |
2012年 | 33篇 |
2011年 | 31篇 |
2010年 | 27篇 |
2009年 | 34篇 |
2008年 | 37篇 |
2007年 | 23篇 |
2006年 | 28篇 |
2005年 | 32篇 |
2004年 | 31篇 |
2003年 | 13篇 |
2002年 | 18篇 |
2001年 | 21篇 |
2000年 | 25篇 |
1999年 | 17篇 |
1998年 | 15篇 |
1997年 | 18篇 |
1996年 | 14篇 |
1995年 | 7篇 |
1994年 | 14篇 |
1993年 | 10篇 |
1992年 | 14篇 |
1991年 | 14篇 |
1990年 | 12篇 |
1989年 | 8篇 |
1988年 | 9篇 |
1987年 | 12篇 |
1986年 | 17篇 |
1985年 | 6篇 |
1984年 | 6篇 |
1983年 | 7篇 |
1982年 | 8篇 |
1981年 | 4篇 |
1980年 | 10篇 |
1979年 | 8篇 |
1978年 | 9篇 |
1977年 | 7篇 |
1976年 | 4篇 |
1975年 | 5篇 |
1969年 | 4篇 |
1963年 | 3篇 |
排序方式: 共有1075条查询结果,搜索用时 31 毫秒
1.
Stephen J. Ruberg Frank E. Harrell Jr. Margaret Gamalo-Siebers Lisa LaVange J. Jack Lee Karen Price 《The American statistician》2019,73(1):319-327
ABSTRACTThe cost and time of pharmaceutical drug development continue to grow at rates that many say are unsustainable. These trends have enormous impact on what treatments get to patients, when they get them and how they are used. The statistical framework for supporting decisions in regulated clinical development of new medicines has followed a traditional path of frequentist methodology. Trials using hypothesis tests of “no treatment effect” are done routinely, and the p-value < 0.05 is often the determinant of what constitutes a “successful” trial. Many drugs fail in clinical development, adding to the cost of new medicines, and some evidence points blame at the deficiencies of the frequentist paradigm. An unknown number effective medicines may have been abandoned because trials were declared “unsuccessful” due to a p-value exceeding 0.05. Recently, the Bayesian paradigm has shown utility in the clinical drug development process for its probability-based inference. We argue for a Bayesian approach that employs data from other trials as a “prior” for Phase 3 trials so that synthesized evidence across trials can be utilized to compute probability statements that are valuable for understanding the magnitude of treatment effect. Such a Bayesian paradigm provides a promising framework for improving statistical inference and regulatory decision making. 相似文献
2.
Time, Self, and the Curiously Abstract Concept of Agency* 总被引:2,自引:0,他引:2
The term "agency" is quite slippery and is used differently depending on the epistemological roots and goals of scholars who employ it. Distressingly, the sociological literature on the concept rarely addresses relevant social psychological research. We take a social behaviorist approach to agency by suggesting that individual temporal orientations are underutilized in conceptualizing this core sociological concept. Different temporal foci—the actor's engaged response to situational circumstances—implicate different forms of agency. This article offers a theoretical model involving four analytical types of agency ("existential,""identity,""pragmatic," and "life course") that are often conflated across treatments of the topic. Each mode of agency overlaps with established social psychological literatures, most notably about the self, enabling scholars to anchor overly abstract treatments of agency within established research literatures. 相似文献
3.
Two habituation experiments were conducted to investigate how 4‐month‐old infants perceive partly occluded shapes. In the first experiment, we presented a simple, partly occluded shape to the infants until habituation was reached. Then we showed either a probable completion (one that would be predicted on the basis of both local and global cues) or an improbable completion. Longer looking times were found for the improbably completed shape (compared to probable and control conditions), suggesting that the probable shape was perceived during partial occlusion. In the second experiment, infants were habituated to more ambiguous partly occluded shapes, where local and global cues would result in different completions. For adults, the percept of these shapes is usually dominated by global influences. However, after habituation the infants looked longer at the globally completed shapes. These results suggest that by the age of 4 months, infants are able to infer the perceptual completion of partly occluded shapes, but for more ambiguous shapes, this completion seems to be dominated by local influences. 相似文献
4.
5.
THE MYSTERIOUS DISAPPEARANCE OF BATTERED WOMEN IN FAMILY THERAPISTS' OFFICES: MALE PRIVILEGE COLLUDING WITH MALE VIOLENCE 总被引:2,自引:1,他引:1
Family therapy has not served battered women well. Men use battering to silence women; a woman, once abused, is unlikely to speak honestly in a situation where doing so invites re-abuse. Therefore we rarely perceive, label or deal effectively with male violence toward women, a major source of marital disruption. To stand with the oppressed, we must learn to detect the possibility of abuse, separate the couple, and refuse to collude with criminal acts. 相似文献
6.
Projecting losses associated with hurricanes is a complex and difficult undertaking that is wrought with uncertainties. Hurricane Charley, which struck southwest Florida on August 13, 2004, illustrates the uncertainty of forecasting damages from these storms. Due to shifts in the track and the rapid intensification of the storm, real-time estimates grew from 2 to 3 billion dollars in losses late on August 12 to a peak of 50 billion dollars for a brief time as the storm appeared to be headed for the Tampa Bay area. The storm hit the resort areas of Charlotte Harbor near Punta Gorda and then went on to Orlando in the central part of the state, with early poststorm estimates converging on a damage estimate in the 28 to 31 billion dollars range. Comparable damage to central Florida had not been seen since Hurricane Donna in 1960. The Florida Commission on Hurricane Loss Projection Methodology (FCHLPM) has recognized the role of computer models in projecting losses from hurricanes. The FCHLPM established a professional team to perform onsite (confidential) audits of computer models developed by several different companies in the United States that seek to have their models approved for use in insurance rate filings in Florida. The team's members represent the fields of actuarial science, computer science, meteorology, statistics, and wind and structural engineering. An important part of the auditing process requires uncertainty and sensitivity analyses to be performed with the applicant's proprietary model. To influence future such analyses, an uncertainty and sensitivity analysis has been completed for loss projections arising from use of a Holland B parameter hurricane wind field model. Uncertainty analysis quantifies the expected percentage reduction in the uncertainty of wind speed and loss that is attributable to each of the input variables. 相似文献
7.
8.
Modeling for Risk Assessment of Neurotoxic Effects 总被引:2,自引:0,他引:2
The regulation of noncancer toxicants, including neurotoxicants, has usually been based upon a reference dose (allowable daily intake). A reference dose is obtained by dividing a no-observed-effect level by uncertainty (safety) factors to account for intraspecies and interspecies sensitivities to a chemical. It is assumed that the risk at the reference dose is negligible, but no attempt generally is made to estimate the risk at the reference dose. A procedure is outlined that provides estimates of risk as a function of dose. The first step is to establish a mathematical relationship between a biological effect and the dose of a chemical. Knowledge of biological mechanisms and/or pharmacokinetics can assist in the choice of plausible mathematical models. The mathematical model provides estimates of average responses as a function of dose. Secondly, estimates of risk require selection of a distribution of individual responses about the average response given by the mathematical model. In the case of a normal or lognormal distribution, only an estimate of the standard deviation is needed. The third step is to define an adverse level for a response so that the probability (risk) of exceeding that level can be estimated as a function of dose. Because a firm response level often cannot be established at which adverse biological effects occur, it may be necessary to at least establish an abnormal response level that only a small proportion of individuals would exceed in an unexposed group. That is, if a normal range of responses can be established, then the probability (risk) of abnormal responses can be estimated. In order to illustrate this process, measures of the neurotransmitter serotonin and its metabolite 5-hydroxyindoleacetic acid in specific areas of the brain of rats and monkeys are analyzed after exposure to the neurotoxicant methylene-dioxymethamphetamine. These risk estimates are compared with risk estimates from the quantal approach in which animals are classified as either abnormal or not depending upon abnormal serotonin levels. 相似文献
9.
An alternative to farmer age as an indicator of life-cycle stage: The case for a farm family age index 总被引:2,自引:0,他引:2
In studies of farming, the age of the principal decision-maker (PDM) has been associated with numerous farm structural and managerial features and has been widely accepted as a good indicator of the influence of life-cycle factors on decision-making. As such, it has become an important aspect of many quantitative studies of agricultural change. However, contemporary studies of family farming demonstrate that the concept of a single PDM in family farms is becoming an anachronism as alternative enterprises, pluriactivity and the scale of family farms force more diffuse management/operating systems. This raises questions concerning whether the age of the PDM can still be taken as representative of farm structure, strategy or life-cycle stage? Using a study conducted in the Grampian Mountains region of Scotland in 2003 this note investigates the impact of using an alternative index—compiled by averaging the age of family members working on the farm. It suggests that PDM age is a relatively poor indicator of farm structural and managerial features compared to a family age index and calls for researchers to think about alternative approaches to measuring ‘age’ as an indicator. 相似文献
10.