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991.
Elimination of a nuisance variable is often non‐trivial and may involve the evaluation of an intractable integral. One approach to evaluate these integrals is to use the Laplace approximation. This paper concentrates on a new approximation, called the partial Laplace approximation, that is useful when the integrand can be partitioned into two multiplicative disjoint functions. The technique is applied to the linear mixed model and shows that the approximate likelihood obtained can be partitioned to provide a conditional likelihood for the location parameters and a marginal likelihood for the scale parameters equivalent to restricted maximum likelihood (REML). Similarly, the partial Laplace approximation is applied to the t‐distribution to obtain an approximate REML for the scale parameter. A simulation study reveals that, in comparison to maximum likelihood, the scale parameter estimates of the t‐distribution obtained from the approximate REML show reduced bias.  相似文献   
992.
This article examines the Program Assessment Rating Tool (PART)in the federal budgeting process. The early evidence on PARTprompts the search for a theory of budgeting that accepts thatperformance information will influence decisions but will notbe used in the same way from decision to decision, as the espousedtheory of performance budgeting suggests. Dialogue theory emphasizesthe ambiguity of performance information and related resourceallocation choices. An exploratory test of dialogue theory isundertaken through an experiment involving graduate studentsassessing PART evaluations. The results illustrate a varietyof ways in which different individuals can examine the sameprogram and, using logical warrants, come to different conclusionsabout performance and future funding requirements.  相似文献   
993.
This study tested the association between mother’s early age at first birth and various life outcomes for her children in later adolescence and early adulthood. Data were analyzed from the Rochester Youth Development Study, an ongoing panel study of adolescents enrolled in seventh or eighth grade in Rochester Public Schools in 1988 (N =729). Boys born to mothers who began childbearing before age 19 had elevated risks of drug use, gang membership, unemployment, and early parenthood. Girls born to young mothers only had elevated risks of early parenthood. Of the mediators tested, low maternal education had the largest mediating effects. The findings suggest that the risks associated with being born to a young mother are substantial but perhaps disproportionately so for boys.  相似文献   
994.
995.
This study examined whether the prevalence of self-reportedhealth risk behaviors among high school students varied by surveysetting (school versus home) and mode of administration (paperand pencil versus computer). Students in grades 9 and 11 wereassigned randomly to one of four conditions—school paper-and-pencilinstrument (PAPI), school computer-assisted self-interview (CASI),home PAPI, and home CASI. During the spring of 2004, 4,506 studentscompleted identically worded questionnaires based on the YouthRisk Behavior Survey questionnaire. Logistic regression analysescontrolling for sex, grade, and race/ethnicity revealed thatsetting was associated significantly with the reporting of 30of the 55 risk behaviors examined, and mode was associated significantlywith the reporting of 7 of the 55 behaviors. For all behaviorswith a significant setting main effect, the odds of reportingthe behavior were greater among students who completed questionnairesat school than among students who completed questionnaires athome. For all behaviors with a significant mode main effect,PAPI mode students had lower odds of reporting the behaviorthan CASI mode students. Because social measurement researchassumes that higher prevalence estimates are more valid thanlower estimates, methodological factors shown to increase estimates,such as setting and mode, should be considered when planningsurveys.  相似文献   
996.
Models of incomplete information have played a major role in the fields of political science and political economy. The models have almost exclusively been signaling models, and their substantive focus is frequently on situations in which the extensive form is not dictated by institutional requirements or procedures. We explore the relation between multiple-sender signaling games and the corresponding screening or mechanism design games without transfers and establish an equivalence result. If there is a fully-revealing equilibrium in the signaling game there is also a full-information optimal mechanism that yields the principal’s optimal policy in every state. The converse, that fully-revealing equilibria exist in the signaling game if a full-information optimal mechanism exists, is true if and only if the mechanism involves only the selection of policies that are optimal for some belief about the state. We also present two straightforward sufficient conditions for the existence of full-information optimal mechanisms. When either holds, fully-revealing equilibria in the signaling and screening games exist. The perceived advantage of the signaling over the screening approach – that no commitment by the principal is assumed – may be over-stated as flexibility in specifying off the path beliefs can mimic commitment.  相似文献   
997.
A team building activity, the image exchange, was helpful to interdisciplinary teams in clarifying perceptions and opinions of participants about the roles of each discipline (child welfare, domestic violence, mental health, and substance abuse workers) at a five-day interdisciplinary training workshop. Discussion of team members’ perceptions and views provided opportunities to develop insights about misperceptions. Training in team development and role clarification provided a foundation for the development of effective interdisciplinary collaboration, which may improve interdisciplinary practice.Dr. Packard is an Associate Professor and Dr. Jones is a Professor in the School of Social Work at SDSU. At the time of writing, Ms. Nahrstedt was a Research Assistant in the School of Social Work at SDSU. This project was funded by a grant from the U.S. Department of Health and Human Services, Administration for Children, Youth, and Families.  相似文献   
998.
The success of the Global Polio Eradication Initiative promises to bring large benefits, including sustained improvements in quality of life (i.e., cases of paralytic disease and deaths avoided) and costs saved from cessation of vaccination. Obtaining and maintaining these benefits requires that policymakers manage the transition from the current massive use of oral poliovirus vaccine (OPV) to a world without OPV and free of the risks of potential future reintroductions of live polioviruses. This article describes the analytical journey that began in 2001 with a retrospective case study on polio risk management and led to development of dynamic integrated risk, economic, and decision analysis tools to inform global policies for managing the risks of polio. This analytical journey has provided several key insights and lessons learned that will be useful to future analysts involved in similar complex decision-making processes.  相似文献   
999.
1000.
This paper explores current trends in religious practice, observance and belief in Ulster Protestantism for elements of continuity and change. Using historical and survey data it is clear that there are strong elements of both. However, Protestant religiosity is not changing to the point that it constitutes secularisation, as sociologists of religion understand it. Nor are new trends in religiosity weakening ethno‐national identities in Northern Ireland. This is because political identities are socially reproduced in ways that are independent of their religious roots and are thus unaffected by patterns of religiosity. Likely changes in Protestant religiosity in the future therefore offer no immediate panacea for altering the dynamics of Northern Irish politics.  相似文献   
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