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131.
132.
Story stem measures are an increasingly popular method for assessing the attachment representations of young children, but little is known of their cross‐cultural applicability. This study aimed to characterise the attachment representations in 73 five‐ to eight‐year‐old children in urban Ghana, West Africa, using the Manchester Child Attachment Story Task (MCAST) to test its feasibility, psychometric characteristics and concurrent associations with caregiver‐ and teacher‐rated child behaviour, and to conduct a qualitative thematic analysis of methodological observations. Among the classifiable cases (92 percent), all attachment classifications were observed, yielding a higher rate of secure attachment than in European samples. Inter‐rater reliability, internal consistency, and internal structure were reasonable and largely similar to European studies, although one structural difference was the separation of ‘child assuagement of distress’ from other secure‐related items. MCAST narratives were associated with teacher‐ and caregiver‐rated hyperactivity, but internal consistency was low in most Strengths and Difficulties Questionnaire scales. Possible culturally‐sensitive explanations for our psychometric and qualitative findings are discussed. Overall, story stems are a promising tool for accessing attachment representations in non‐Western samples, although modifications are likely to improve cross‐cultural equivalence when applied to non‐Western cultures. Further investigation is needed to link MCAST outcomes to parenting and socio‐emotional development.  相似文献   
133.
Urban Ecosystems - Urbanization may negatively affect forest obligate bat species. We compared the roosting behavior of federally endangered Indiana bats (Myotis sodalis) in a fragmented site,...  相似文献   
134.
A set S of vertices of a graph G is a total outer-connected dominating set if every vertex in V(G) is adjacent to some vertex in S and the subgraph induced by V?S is connected. The total outer-connected domination number γ toc (G) is the minimum size of such a set. We give some properties and bounds for γ toc in general graphs and in trees. For graphs of order n, diameter 2 and minimum degree at least 3, we show that $\gamma_{toc}(G)\le \frac{2n-2}{3}$ and we determine the extremal graphs.  相似文献   
135.
Many large organizations use a stage‐gate process to manage new product development projects. In a typical stage‐gate process project managers learn about potential ideas from research and exert effort in development while senior executives make intervening go/no‐go decisions. This decentralized decision making results in an agency problem because the idea quality in early stages is unknown to the executive and the project manager must exert unobservable development effort in later stages. In light of these challenges, how should the firm structure incentives to ensure that project managers reveal relevant information and invest the appropriate effort to create value? In this study, we develop a model of adverse selection in research and moral hazard in development with a go/no‐go decision at the intervening gate. Our results show that the principal's uncertainty regarding early‐stage idea quality—a term we refer to as idea risk—alters the effect of late‐stage development risk. The presence of idea risk can alter the incentives offered to the agent and may lead the principal to reject projects that otherwise seem favorable in terms of positive net present value. A simulation of early‐stage ideas, found through search on a complex landscape, shows that the firm can mitigate the negative effects of idea risk by encouraging breadth of search and high tolerance for failure.  相似文献   
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137.
Pandemic influenza represents a serious threat not only to the population of the United States, but also to its economy. In this study, we analyze the total economic consequences of potential influenza outbreaks in the United States for four cases based on the distinctions between disease severity and the presence/absence of vaccinations. The analysis is based on data and parameters on influenza obtained from the Centers for Disease Control and the general literature. A state‐of‐the‐art economic impact modeling approach, computable general equilibrium, is applied to analyze a wide range of potential impacts stemming from the outbreaks. This study examines the economic impacts from changes in medical expenditures and workforce participation, and also takes into consideration different types of avoidance behavior and resilience actions not previously fully studied. Our results indicate that, in the absence of avoidance and resilience effects, a pandemic influenza outbreak could result in a loss in U.S. GDP of $25.4 billion, but that vaccination could reduce the losses to $19.9 billion. When behavioral and resilience factors are taken into account, a pandemic influenza outbreak could result in GDP losses of $45.3 billion without vaccination and $34.4 billion with vaccination. These results indicate the importance of including a broader set of causal factors to achieve more accurate estimates of the total economic impacts of not just pandemic influenza but biothreats in general. The results also highlight a number of actionable items that government policymakers and public health officials can use to help reduce potential economic losses from the outbreaks.  相似文献   
138.
U.S. airports and airliners are prime terrorist targets. Not only do the facilities and equipment represent high‐value assets, but the fear and dread that is spread by such attacks can have tremendous effects on the U.S. economy. This article presents the methodology, data, and estimates of the macroeconomic impacts stemming from behavioral responses to a simulated terrorist attack on a U.S. airport and on a domestic airliner. The analysis is based on risk‐perception surveys of these two scenarios. The responses relate to reduced demand for airline travel, shifts to other modes, spending on nontravel items, and savings of potential travel expenditures by U.S. resident passengers considering flying domestic routes. We translate these responses to individual spending categories and feed these direct impact results into a computable general equilibrium (CGE) model of the U.S. economy to ascertain the indirect and total impacts on both the airline industry and the economy as a whole. Overall, the estimated impacts on GDP of both types of attacks exceed $10B. We find that the behavioral economic impacts are almost an order of magnitude higher than the ordinary business interruption impacts for the airliner attack and nearly two orders of magnitude higher for the airport attack. The results are robust to sensitivity tests on the travel behavior of U.S. residents in response to terrorism.  相似文献   
139.
The good government models of the 1990s realized a focus that included reinventing, reengineer-ing, rethinking, quality, empowerment, and devolution of the organization. These organizational reform ideologies sought to increase involvement, improve productivity, manage performance, and drive results. One essential key that has been disregarded in these government models is the involvement of community in the decision-making process. This paper points to the importance of involving and empowering citizens in the decision-making process, particularly in regard to community justice based on the notion of restorative justice system. Community justice, a modern day reform movement with international proportions, is based on the principles of empowering community, repairing harm caused by a crime or disturbance, and reducing risk to the community.  相似文献   
140.
Previous research has shown that under a suitable no‐jump condition, the price of a defaultable security is equal to its risk‐neutral expected discounted cash flows if a modified discount rate is introduced to account for the possibility of default. Below, we generalize this result by demonstrating that one can always value defaultable claims using expected risk‐adjusted discounting provided that the expectation is taken under a slightly modified probability measure. This new probability measure puts zero probability on paths where default occurs prior to the maturity, and is thus only absolutely continuous with respect to the risk‐neutral probability measure. After establishing the general result and discussing its relation with the existing literature, we investigate several examples for which the no‐jump condition fails. Each example illustrates the power of our general formula by providing simple analytic solutions for the prices of defaultable securities.  相似文献   
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