首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   86910篇
  免费   2923篇
  国内免费   3篇
管理学   12010篇
民族学   523篇
人才学   25篇
人口学   6520篇
丛书文集   502篇
理论方法论   9222篇
综合类   2075篇
社会学   40326篇
统计学   18633篇
  2023年   502篇
  2021年   559篇
  2020年   1496篇
  2019年   2194篇
  2018年   2003篇
  2017年   3076篇
  2016年   2310篇
  2015年   2034篇
  2014年   2615篇
  2013年   18782篇
  2012年   2199篇
  2011年   1979篇
  2010年   1888篇
  2009年   2134篇
  2008年   1930篇
  2007年   1722篇
  2006年   2000篇
  2005年   2181篇
  2004年   2078篇
  2003年   1817篇
  2002年   1898篇
  2001年   1876篇
  2000年   1668篇
  1999年   1608篇
  1998年   1458篇
  1997年   1295篇
  1996年   1255篇
  1995年   1287篇
  1994年   1254篇
  1993年   1236篇
  1992年   1204篇
  1991年   1136篇
  1990年   1116篇
  1989年   953篇
  1988年   1053篇
  1987年   934篇
  1986年   821篇
  1985年   996篇
  1984年   1074篇
  1983年   954篇
  1982年   895篇
  1981年   829篇
  1980年   775篇
  1979年   824篇
  1978年   741篇
  1977年   670篇
  1976年   629篇
  1975年   602篇
  1974年   489篇
  1973年   413篇
排序方式: 共有10000条查询结果,搜索用时 593 毫秒
251.
The theory of incapacitation involves reducing an offender's ability or capacity to commit further crimes. Capital punishment accomplishes this goal. An executed murderer never murders again. However, we do not execute all murderers, only capital murderers. This policy produces several research questions. Do capital murderers present a special risk to society? Are capital murderers more likely to murder or commit other violent crimes again than other murderers or the average citizen? To answer these questions, many states require a prediction of future dangerousness of a newly convicted murderer. To what extent has the judgment of future dangerousness matched actuarial data of subsequent murders and serious crimes? Using a secondary analysis, this investigation attempted to assemble available data of postconviction dangerousness of death sentenced capital murderers to create a more comprehensive actuarial account of subsequent dangerousness and to present the data in a common format used by the Federal Bureau of Investigation and the Bureau of Justice Statistics. Across 14 studies identified with relevant data, there were 13 instances of subsequent murder and 462 serious crime or prison rule violations.  相似文献   
252.
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   
253.
By approximating the nonparametric component using a regression spline in generalized partial linear models (GPLM), robust generalized estimating equations (GEE), involving bounded score function and leverage-based weighting function, can be used to estimate the regression parameters in GPLM robustly for longitudinal data or clustered data. In this paper, score test statistics are proposed for testing the regression parameters with robustness, and their asymptotic distributions under the null hypothesis and a class of local alternative hypotheses are studied. The proposed score tests reply on the estimation of a smaller model without the testing parameters involved, and perform well in the simulation studies and real data analysis conducted in this paper.  相似文献   
254.
Although Latinas/os have a long history in the USA and represent a growing percentage of the population, they remain largely invisible or stereotyped in dominant images and discourses. Such representations are often ahistorical, and they camouflage the effects of US power and inequality. However, the spring 2006 immigrant rights demonstrations disturbed dominant conceptions. The demonstrators called attention to the contradictory US practices that disrupt home countries, recruit labor migrants, and deny immigrants full participation. Likewise, the role of students in these demonstrations spurred reflections on why youth would walk out of their schools for immigrant rights. Inspired by these demonstrations, we combine materials from multiple disciplines to emphasize the significance of US imperialism, exploitation, and exclusion on Latina/o migration, education, and activism. Key to this article is a reframing of how the media, K-12 curriculum, and popular discourse often engage in a cultural cover-up that sustains inequality.  相似文献   
255.
Many explanations have been given as to why men batter. Rarely are deep unconscious intrapsychic processes identified as contributing reasons. One way that violent men may use their partner to fill emotional needs is through the primitive defense of projective identification. Projective identification may be invoked by men to induce the other partner to carry split off threatening parts of the self that are too anxiety provoking to retain. The occurrence of projective identification could therefore be an important intrapsychic and interpersonal dynamic that contributes to the escalation of tension prior to the violent episode.  相似文献   
256.
Parameter design or robust parameter design (RPD) is an engineering methodology intended as a cost-effective approach for improving the quality of products and processes. The goal of parameter design is to choose the levels of the control variables that optimize a defined quality characteristic. An essential component of RPD involves the assumption of well estimated models for the process mean and variance. Traditionally, the modeling of the mean and variance has been done parametrically. It is often the case, particularly when modeling the variance, that nonparametric techniques are more appropriate due to the nature of the curvature in the underlying function. Most response surface experiments involve sparse data. In sparse data situations with unusual curvature in the underlying function, nonparametric techniques often result in estimates with problematic variation whereas their parametric counterparts may result in estimates with problematic bias. We propose the use of semi-parametric modeling within the robust design setting, combining parametric and nonparametric functions to improve the quality of both mean and variance model estimation. The proposed method will be illustrated with an example and simulations.  相似文献   
257.
258.
Objective. The risk compensation hypothesis suggests that drivers enjoying greater safety will drive more recklessly and thereby impose greater risks on nonoccupants. We provide a test of the risk compensation hypothesis in the context of state seatbelt laws and belt use rates. Methods. Fixed‐effects models with policy and demographic variables are estimated using annual state data from 1985 to 2002 to test the effect of seatbelt laws and seatbelt use rates on logged fatality rates for occupants, pedestrians, motorcyclists, and all nonoccupants in separate models. Results. Contrary to the risk compensation hypothesis, the results indicate that both occupants and nonoccupants enjoy greater safety due to state mandatory use laws and increased safety belt use rates. Conclusion. Overall, seatbelt laws and the higher belt use these laws induce do not increase nonoccupant risk exposure. If anything, these laws and the accompanying increase in belt use result in safer driving behavior.  相似文献   
259.
In the last 10 years, interest in the concept of stigma has grown remarkably throughout the social sciences. Today, stigma is an important topic that bridges many disciplines, including sociology, psychology, social psychology, and public health. This literature review primarily addresses perceptions of and responses to stigma from the insider's or target's perspective. The topics examined in this review include the following: defining stigma, public opinion and attitudes toward the stigmatized, measurement of perceptions of stigma and discrimination, the coping strategies employed by stigmatized persons to deal with stigma, the impact of stigma in terms of psychological and behavioral outcomes, explanations of coping strategies and outcomes, and strategies and interventions to reduce stigma. As many of the concerns faced by stigmatized persons are universal, what has been learned in research about one stigmatized group can provide insight into another. Promising directions for future stigma-related research are identified and discussed.  相似文献   
260.
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   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号