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111.
As part of its periodic re-evaluation of particulate matter (PM) standards, the U.S. Environmental Protection Agency estimated the health risk reductions associated with attainment of alternative PM standards in two locations in the United States with relatively complete air quality data: Philadelphia and Los Angeles. PM standards at the time of the analysis were defined for particles of aerodynamic diameter less than or equal to 10 microm, denoted as PM-10. The risk analyses estimated the risk reductions that would be associated with changing from attainment of the PM-10 standards then in place to attainment of alternative standards using an indicator measuring fine particles, defined as those particles of aerodynamic diameter less than or equal to 2.5 microm and denoted as PM-2.5. Annual average PM-2.5 standards of 12.5, 15, and 20 microg/m3 were considered in various combinations with daily PM-2.5 standards of 50 and 65 microg/m3. Attainment of a standard or set of standards was simulated by a proportional rollback of "as is" daily PM concentrations to daily PM concentrations that would just meet the standard(s). The predicted reductions in the incidence of health effects varied from zero, for those alternative standards already being met, to substantial reductions of over 88% of all PM-associated incidence (e.g., in mortality associated with long-term exposures in Los Angeles, under attainment of an annual standard of 12.5 microg/m3). Sensitivity analyses and integrated uncertainty analyses assessed the multiple-source uncertainty surrounding estimates of risk reduction.  相似文献   
112.
It has been argued that traders use their natural sensitivity to the fractal properties of price graphs to assess risk and that they are better able to do this when given price change as well as price level information. This approach implies that risk assessments should be higher when the Hurst exponents are lower, that this relationship should be stronger in the presence of price change information and that risk assessment should depend more strongly on the Hurst exponent than on the standard deviation of the series. Participants in Experiment 1 decided which of two assets was riskier by inspecting graphs of their price series. Graphs with lower Hurst exponents were selected only by those who were less emotionally stable and hence more sensitive to risk. However, when both price series and price change series were presented, the assets with lower Hurst exponents were selected by all participants. In a second experiment, participants were given both price level and price change series for a number of assets and rated the risk of trading in each one. Ratings depended more strongly on Hurst exponents than on other measures of volatility. They also depended on indicators of potential loss. Human risk assessment deviates from the way that risk is measured in modern finance theory: it requires integration of information relevant to both uncertainty and loss aversion, thereby imposing high attentional demands on traders. These demands may impair risk assessment but they can be eased by adding displays of price change information.  相似文献   
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Abstract

This article examines adolescent reports of parental mediation of hip-hop music videos, a medium that has been celebrated for its artistry and empowering youth, yet criticized for stereotyped portrayals of women and men. Survey data of 315 adolescents (M age?=?15.2, SD?=?1.73) investigated the relationship between adolescent reports of viewing hip-hop music videos, parent-child communication about these videos, and attitudes about gender and the music videos. Respondents reported low levels of both positive and negative parental mediation of hip-hop music videos, yet when they occurred, reports of negative mediation positively predicted critical attitudes about these videos.  相似文献   
115.
本文从人文知识的角度出发对当今的政治理解提出了两项改进意见:其一要重温柏拉图和亚里士多德思想中有关thumos的观念,其二是在政治科学中像人文科学那样运用名称.thumos乃是一种对身体有意识但却不受其束缚的人之科学的一个基础,它具有丰富的内涵:它是生气与收益之间的对比,这意味着政治乃是何者使你生气的问题;它是对胜利的坚持,这意味着政治所产生的是胜利者和失败者;它象征着一个人对动物性身体所特有的个人自己所做的精神层面的捍卫,代表了一种动物在面临威胁或可能的威胁的时候所做的剧烈回应;此外,它也体现了派性的顽固、自信的作用、个体自己的常在、宗教的任务、个殊性的结果和关于伟大的抱负等等.从另一方面来看,如果我们要想理解人的(政治)行为,特别是理解我们在thumos中所见到的对人之个殊性的特别坚持,那么我们就必须承认人的名称,重视名称在政治科学中的价值.  相似文献   
116.
Summary.  The recently introduced national pupil database in England allows the tracking of every child through the compulsory phases of the state education system. The data from key stage 2 for three local education authorities are studied, following cohorts of pupils through their schooling. The mobility of pupils among schools is studied in detail by using multiple-membership multilevel models that include prior achievement and other predictors and the results are compared with traditional 'value-added' approaches that ignore pupil mobility. The analysis also includes a cross-classification of junior and infant schools attended. The results suggest that some existing conclusions about schooling effects may need to be revised.  相似文献   
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After ten years of rapid, if sometimes chaotic growth, it is time to reflect upon where Decision Sciences is headed. At stake are the essential questions of (1) should the growth of the discipline be managed, and if so (2) how should it be managed and who should do the managing? I argue that the growth of the discipline should be managed rather than be dictated by the technological imperative that states that any envisioned application of quantitative methods should be implemented. Moreover, I argue that, since to a large degree the implementation decision is an ethical question, the individual decision scientist must ultimately be held accountable. Finally, I suggest that Glenn Stassen's social ethic paradigm may be a useful vehicle for resolving intradiscipline conflicts. These abstract ideas are concretized by examining the growth of the area of artificial intelligence.  相似文献   
119.
Abstract

Identity fusion — a visceral feeling of connection with a group — is a powerful predictor of willingness to engage in extreme pro-group behaviour. Here we propose that identity fusion also reinforces willingness to fight and die for one’s siblings, and we explore one of the underlying mechanisms producing this effect. We additionally controlled for a powerful predictor of family investment, perceived psychological similarity with the sibling. Our study shows that fusion with a sibling, but not perceived similarity, is positively associated with willingness to fight and die for the sibling. This relation is mediated by the imagined personal consequences of losing one’s sibling. This research extends previous work on fusion with groups to pairs of individuals and identifies a new mediator of the effect of fusion on willingness to fight and die for others. Overall, these results suggest that identity fusion might contribute towards explaining self-sacrifice among genetically related individuals as predicted by the theory of kin selection.  相似文献   
120.
To explore the variation of predictors of relapse in treatment and support seeking gamblers. A prospective cohort study with 158 treatment and support seeking problem gamblers in South Australia. Key measures were selected using a consensus process with international experts in problem gambling and related addictions. The outcome measures were Victorian Gambling Screen (VGS) and behaviours related to gambling. Potential predictors were gambling related cognitions and urge, emotional disturbance, social support, sensation seeking traits, and levels of work and social functioning. Mean age of participants was 44 years (SD = 12.92 years) and 85 (54 %) were male. Median time for participants enrolment in the study was 8.38 months (IQR = 2.57 months). Patterns of completed measures for points in time included 116 (73.4 %) with at least a 3 month follow-up. Using generalised mixed-effects regression models we found gambling related urge was significantly associated with relapse in problem gambling as measured by VGS (OR 1.29; 95 % CI 1.12–1.49) and gambling behaviours (OR 1.16; 95 % CI 1.06–1.27). Gambling related cognitions were also significantly associated with VGS (OR 1.06; 95 % CI 1.01–1.12). There is consistent association between urge to gamble and relapse in problem gambling but estimates for other potential predictors may have been attenuated because of methodological limitations. This study also highlighted the challenges presented from a cohort study of treatment and support seeking problem gamblers.  相似文献   
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