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941.
Rapid advances of information technology in recent years have enabled both the manufacturers and the retailers to operate their own Internet channels. In this study, we investigate the interaction between the capabilities of introducing the Internet channels, the pricing strategies, and the channel structure. We classify consumers into two segments: grocery shoppers attach a higher utility from purchasing through the physical channel, whereas a priori Internet shoppers prefer purchasing online. We find that when the Internet shoppers are either highly profitable or fairly unimportant, the manufacturer prefers to facilitate the channel separation either through his own Internet channel or the retailer's. In the intermediate region, however, the manufacturer encroaches the grocery shoppers and steals the demand from the retailer's physical channel. With horizontal competition between retailers, a priori symmetric retailers may adopt different channel strategies as a stable market equilibrium. The manufacturer may willingly give up his Internet channel and leverage on the retailer competition. When the manufacturer sells through an online e‐tailer, Internet shoppers may be induced to purchase through the physical channel. This reverse encroachment strategy emerges because selling through the e‐tailer leads to a more severe double marginalization problem.  相似文献   
942.
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   
943.
Humanitarian supply chains involve many different entities, such as government, military, private, and non‐governmental organizations and individuals. Well‐coordinated interactions between entities can lead to synergies and improved humanitarian outcomes. Information technology (IT) tools can help facilitate collaboration, but cost and other barriers have limited their use. We document the use of an IT tool to improve last‐mile supply distribution and data management in one of many camps for internally displaced persons after the January 2010 earthquake in Haiti, and we describe other current uses of technology in camp management. Motivated by these examples and the interest among humanitarian organizations in expanding the use of such tools to facilitate coordination, we introduce a cooperative game theory model and explore insights about the conditions under which multi‐agency coordination is feasible and desirable. We also outline an agenda for future research in the area of technology‐enabled collaboration in the humanitarian sector.  相似文献   
944.
945.
Measuring trends in child well-being: an evidence-based approach   总被引:6,自引:0,他引:6  
This paper first reviews the goals of the founding documents of the social indicators and quality-of-life movements of the 1960s and 1970s. It next describes the current state of knowledge with respect to the founding goals of this field. The focus then turns to the topic of measuring changes in child and youth well-being in the United States over the past few decades. In particular, the evidence-based approach used in the construction of the recently developed composite Child and Youth Well-Being Index (CWI) is described. Some findings from the CWI regarding changes in child and youth well-being in the period 1975–2004 are reported. Trends in the CWI then are compared with data on trends in subjective well-being of high school seniors – similarities of trends in these two series provide validating support for the interpretation of the CWI as an index of changes in the quality-of-life of children and youth. Using data on some additional indicator series, most of which were initiated in the 1990s, an Expanded CWI is then described. The qualitative pattern of change in the expanded CWI is shown to be similar to that of the basic CWI, except that the expanded CWI shows a more pronounced decline in the early-1990s and a slower rate of improvement into the early-2000s. The paper concludes with some possible directions for future work. Revision of a paper presented at the Measuring Child Well-Being: The Pros and Cons of Composite Indices Session, American Statistical Association Annual Meeting, Minneapolis, MN, August 7–11, 2005. We thank Kristin Moore for useful comments. The research on the Child and Youth Well-Being Index reported herein was supported by a grant from the Foundation for Child Development.  相似文献   
946.
Economic and rational‐choice theories suggest that individuals form unions or have children because these decisions increase their subjective well‐being or “happiness.” We investigate this relation using within‐MZ (identical) twin pair estimates to control for unobserved factors, such as optimistic preferences, that may simultaneously affect happiness, partnerships, and fertility. Our findings, based on Danish twins aged 25–45 and 50–70 years old, include the following. (1) Currently being in a partnership has large positive effects on happiness. (2) A first child substantially increases well‐being, in analyses without controls for partnerships, and males enjoy an almost 75 percent larger happiness gain from a first‐born son than from a first‐born daughter; however, only females enjoy a happiness gain from the first‐born child with controls for partnerships. (3) Additional children beyond the first child have a negative effect on subjective well‐being for females, while there is no effect for males. (4) Ever having had children does not significantly affect the subjective well‐being of males or females aged 50–70 years.  相似文献   
947.
948.
Black D  Gates G  Sanders S  Taylor L 《Demography》2000,37(2):139-154
This work provides an overview of standard social science data sources that now allow some systematic study of the gay and lesbian population in the United States. For each data source, we consider how sexual orientation can be defined, and we note the potential sample sizes. We give special attention to the important problem of measurement error, especially the extent to which individuals recorded as gay and lesbian are indeed recorded correctly. Our concern is that because gays and lesbians constitute a relatively small fraction of the population, modest measurement problems could lead to serious errors in inference. In examining gays and lesbians in multiple data sets we also achieve a second objective: We provide a set of statistics about this population that is relevant to several current policy debates.  相似文献   
949.

Volume contents

Contents of Volume 70  相似文献   
950.
Both population aging and the socioeconomic changes that often accompany it have effects on intergenerational arrangements. As a result, assessing the evolving social contract among family members is a key part of the research agenda. Studies monitoring these effects and other consequences are relatively new. Another way to gain insight is through a historical analysis that (a) traces how expectations for old‐age support have changed over recent decades for cohorts advancing through their life cycle, and (b) measures how well expectations accord with actual patterns. This article uses a series of fertility surveys in Taiwan from 1965 to the 1990s to trace expectations for coresidence among cohorts of young married women and to compare these expectations with the actual living arrangements observed in surveys of the elderly in the 1990s. The results indicate sharp shifts in expectations for each of the cohorts as they aged. These shifts reflect a response to respondents' own life course events and the changing socioeconomic environment and show large and persistent differentials by education throughout the period. These factors tend to bring expectations into fairly close concordance with the actual living arrangements observed some years later.  相似文献   
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