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   438篇
  免费   26篇
管理学   49篇
民族学   2篇
人口学   38篇
理论方法论   65篇
综合类   4篇
社会学   281篇
统计学   25篇
  2023年   8篇
  2022年   1篇
  2021年   6篇
  2020年   6篇
  2019年   25篇
  2018年   17篇
  2017年   29篇
  2016年   19篇
  2015年   13篇
  2014年   17篇
  2013年   69篇
  2012年   20篇
  2011年   15篇
  2010年   17篇
  2009年   11篇
  2008年   22篇
  2007年   23篇
  2006年   18篇
  2005年   19篇
  2004年   11篇
  2003年   2篇
  2002年   11篇
  2001年   9篇
  2000年   3篇
  1999年   5篇
  1998年   4篇
  1997年   3篇
  1996年   4篇
  1995年   5篇
  1994年   5篇
  1993年   5篇
  1992年   1篇
  1991年   1篇
  1990年   4篇
  1989年   6篇
  1988年   4篇
  1986年   1篇
  1985年   2篇
  1984年   2篇
  1983年   1篇
  1982年   6篇
  1981年   1篇
  1980年   2篇
  1979年   2篇
  1977年   3篇
  1976年   1篇
  1973年   2篇
  1967年   1篇
  1966年   2篇
排序方式: 共有464条查询结果,搜索用时 640 毫秒
451.
Objectives. The primary goal of this article is to examine factors associated with grandparent care giving within the American Indian/Alaska Native (AIAN) population. Methods. Data from the 2000 Census of Population, 5% Public Use Microdata Sample, are used to evaluate a multivariate logistic regression model focusing on living with and caring for grandchildren. Particular emphasis is placed on characteristics that may reflect culturally‐based ideas about grandparents' responsibility for the care of their grandchildren. Results. Indicators related to Native‐American identity—specifically, reporting race as AIAN only rather than mixed race, reporting tribal membership, and living in a nonmetropolitan area of an “Indian” state—increase the likelihood of being responsible for a grandchild among Native‐American singles and couples aged 45 and over. Conclusions. Cultural and resource characteristics combine to produce high levels of grandparent care giving within the AIAN population. Inasmuch as those with lower educational and economic resources are especially likely to have responsibility for a grandchild, special attention should be directed toward ensuring adequate support for these caregivers.  相似文献   
452.
Two Bayes-type procedures for estimating a multinomial cell probabilities vector, P, in the presence of linear constraints on the parameters are proposed and illustrated by examples from contingency table analysis. Estimation under log-linear constraints is also considered.  相似文献   
453.
This article reports on results of a one-day public health survey conducted in six states by homeless youth providers to measure and compare risk factors between lesbian, gay, and bisexual (LGB) homeless youth and non-LGB homeless youth. This article intends to inform the child welfare field on existing gaps in services and areas where more training and technical support is necessary in providing services to homeless LGB youth. The findings point to substantial differences within the homeless youth sample and demonstrate that in addition to the public health risks young people face merely by being homeless, the risks are exacerbated for those who self-identify as lesbian, gay, or bisexual. The article informs child welfare providers and policymakers about the substantial vulnerability of LGB youth beyond that of non-LGB homeless youth and the need to fund programming, training, technical assistance and further research to specifically respond to the complex needs of this population.  相似文献   
454.
Revenue Management Systems (RMS) are commonly used in the hotel industry to maximize revenues in the short term. The forecasting‐allocation module is a key tactical component of a hotel RMS. Forecasting involves estimating demand for service packages across all stayover nights in a planning horizon. A service package is a unique combination of physical room, amenities, room price, and advance purchase restrictions. Allocation involves parsing the room inventory among these service packages to maximize revenues. Previous research and existing revenue management systems assume the demand for a service package to be independent of which service packages are available for sale. We develop a new forecasting‐allocation approach that explicitly accounts for this dependence. We compare the performance of the new approach against a baseline approach using a realistic hotel RMS simulation. The baseline approach reflects previous research and existing industry practice. The new approach produces an average revenue increase of at least 16% across scenarios that reflect existing industry conditions.  相似文献   
455.
Intergenerational social mobility studies have largely explored the relationship between one aspect of parent background (e.g., education, income, occupational status, wealth, or neighborhood context) and the corresponding aspect of that parent's child once they reach adulthood. Studies examining these various measures have provided differing conclusions about the extent that social origins constrain attainment in the U.S. In contrast, the persistence of racial inequality in intergenerational mobility is one consistent finding. For instance, across various measures, research demonstrates Black individuals are more likely than White individuals to experience downward mobility, and less likely to exceed the socioeconomic standings of their parents. In this article, we argue that a more holistic measure of both origin and destination, one that combines the above-mentioned indicators, is necessary to advance our understanding of the extent that origin constrains future attainment. We summarize lessons gleaned from one-dimensional estimates, and from other approaches that either combine some dimensions of socioeconomic background or attempt to capture a more holistic background in other ways. We then make a recommendation for methodological interventions to accomplish this more holistic approach and conclude with research and policy implications.  相似文献   
456.
Yield management is the dynamic pricing, overbooking, and allocation of perishable assets across market segments in an effort to maximize short-term revenues for the firm. Numerous optimization heuristics for allocation and overbooking exist for the airline industry, whose perishable asset is the airplane seat. When an airplane departs, no revenue is gained from the empty seat(s). In the hotel industry, the perishable asset is the hotel room-once a room is left empty for a night, that night's revenue cannot be recaptured. The literature on yield management heuristics for the hotel industry is sparse. For the hotel operating environment, no research has adequately (1) integrated overbooking with allocation, (2) modeled the phenomenon of hotel patrons extending or contracting their stay at a moment's notice, or (3) performed a realistic performance comparison of alternative heuristics. This research develops (1) two hotel-specific algorithms that both integrate overbooking with the allocation decisions, (2) a simulation model to reproduce realistic hotel operating environments, and (3) compares the performance of five heuristics under 36 realistic hotel operating environments. Seven conclusions are reached with regard to which heuristic(s) perform best in specific operating environments. Generally, heuristic selection is very much dependent on the hotel operating environment. A counterintuitive result is that in many operating environments, the simpler heuristics work as well as the more complex ones.  相似文献   
457.
This mixed-methods study examined how adolescents understand and evaluate different ways to address intergroup harms in schools. In individual interviews, 77 adolescents (M age = 16.49 years; 39 girls, 38 boys) in Bogotá, Colombia, responded to hypothetical vignettes wherein a rival group at school engaged in a transgression against their group. Adolescents reported that students who were harmed should and would talk to school authorities, but also noted they would likely retaliate. In terms of teacher-sanctioned responses to harm, youth endorsed compensation most strongly, followed by apologies, and rated suspension least positively. Youths' explanations for their endorsement of different disciplinary practices reflected varied concerns, including their perceptions of how justice is best achieved and how restoration could be attained.  相似文献   
458.
This study investigated mothers’ and children's constructions of meaning about responsibility for harm in conversations about two experiences when children were hurt by a peer and felt they had either contributed or not contributed to the situation. The sample included 105 Canadian mothers (75% White) and their children (53 girls, 52 boys) across three age groups (M ages = 6.92, 11.14, 15.89 years). Overall, mothers and children emphasized different aspects of responsibility; mothers made more evaluations of acts and discussed the avoidability of harm whereas children referred more to hurtful acts, consequences, reasons, and subsequent responses. Discussions of the child's and peer's responsibility were responsive to the child's perspective on events. The child's responsibility for self-protection was particularly emphasized by mothers and when the child felt they had not contributed to the situation. Children more often mitigated their responsibility as compared to their mothers, and older children referred more to their own and their peer's responsibility for harm. Findings illuminate how conversations with mothers may inform children's judgments of their own and others’ roles in peer conflict.  相似文献   
459.
Group decision making in the presence of multiple conflicting objectives is complex and difficult. This paper describes and evaluates an iterative technique to facilitate multiple objective decision making by multiple decision makers. The proposed method augments an interactive multiobjective optimization procedure with a preference ranking tool and a consensus ranking heuristic. Two multiple objective linear programming (MOLP) solution approaches, the SIMOLP method of Reeves and Franz [39] and the interactive weighted Tchebycheff procedure of Steuer and Choo [49], are recommended optimization strategies to be used independently or in concert. Computational experience suggests that the proposed framework is an effective decision-making tool. The procedure quickly located excellent compromise solutions in a series of test problems with hypothetical decision makers. In addition, human decision makers gave positive evaluations of the procedure and the production plans the procedure provided for a resource allocation case problem.  相似文献   
460.
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