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961.
Devices that integrate multiple functions together are popular in consumer electronic markets. We describe these multifunction devices as fusion products as they fuse together products that traditionally stand alone in the marketplace. In this article, we investigate the manufacturer's fusion product planning decision, adopting a market offering perspective that allows us to address the design and product portfolio decisions simultaneously. The general approach adopted is to develop and analyze a profit‐maximizing model for a single firm that integrates product substitution effects in identifying an optimal market offering. In the general model, we demonstrate that the product design and portfolio decisions are analytically difficult to characterize because the number of possible portfolios can be extremely large. The managerial insight from a stylized all‐in‐one model and numerical analysis is that the manufacturer should, in most cases, select only a subset of fusion and single‐function products to satisfy the market's multidimension needs. This may explain why the function compositions available in certain product markets are limited. In particular, one of the key factors driving the product portfolio decision is the margin associated with the fusion products. If a single all‐in‐one fusion product has relatively high margins, then this product likely dominates the product portfolio. Also, the congruency of the constituent single‐function products is an important factor. When substitution effects are relatively high (i.e., the product set is more congruent), a portfolio containing a smaller number of products is more likely to be optimal.  相似文献   
962.
963.
The theory of global games has shown that coordination games with multiple equilibria may have a unique equilibrium if certain parameters of the payoff function are private information instead of common knowledge. We report the results of an experiment designed to test the predictions of this theory. Comparing sessions with common and private information, we observe only small differences in behavior. For common information, subjects coordinate on threshold strategies that deviate from the global game solution towards the payoff‐dominant equilibrium. For private information, thresholds are closer to the global game solution than for common information. Variations in the payoff function affect behavior as predicted by comparative statics of the global game solution. Predictability of coordination points is about the same for both information conditions.  相似文献   
964.
It is often examined in the literature whether the dividend yields of stocks correlate with their total returns. This paper analyzes the effect of dividend yield on return as well as on risk and on performance of stocks and stock portfolios on the German market. Not only the influence of dividend yield but also of dividend stability is subject to our analysis. Furthermore, tax aspects are considered. However, this study should rather be seen as an empirical analysis of the influence of dividends as a capital market anomaly than a theoretical based validation approach. Our data set comprises daily adjusted stock prices and dividend payment data from the German capital market over the period 3 January 2000–31 July 2008. This period was characterized by a high volatility of the stock market. In addition to the existing literature examining mainly the long-term influence of dividend yields, we also want to find out whether stocks with high and stable dividend payments are able to reduce the risk of a stock investment in short time periods characterized by extreme conditions. We use blue chips (DAX), stocks of medium-sized companies (MDAX), and stocks of technology firms (TecDAX). Our findings suggest that stock performance generally improves with an increasing dividend yield, where this result is actually based on risk reduction instead of a higher return. However, this risk reduction diminishes with an increasing degree of diversification.  相似文献   
965.
Peter Berling   《Omega》2008,36(6):1086
This paper analyzes the multi-period base-stock problem where there is a financial risk associated with a stochastic demand. For the single-period problem, it is known that the optimal inventory policy can be obtained with the Black and Scholes option pricing formula. This paper pushes the analysis further by applying the options valuation framework to the multi-period problem and presenting an algorithm for finding the optimal inventory policy. A computational study indicates that the effect of systematic risk is typically negligible (as for the single-period problem). Therefore, it can be concluded that systematic risk in demand is of little importance for optimal inventory control.  相似文献   
966.
Within the internal ratings-based approach of the New Basel Accord, banks have the possibility to consider the so-called double default effect of guaranteed exposures. However, the correlation assumptions inherent in the regulatory recognition of the double default effect appear to be quite conservative. To evaluate the degree of conservatism, on one hand, the regulatory correlation assumptions are compared with the results of a broad range of empirical studies. On the other hand, additional simulation experiments are carried out. While the comparison with the empirical results indeed suggests that the correlation parameters assumed by the regulatory authorities are much too large, the simulation experiments show that the assumed values are not unrealistic for capturing the intended effects.
Peter GrundkeEmail:
  相似文献   
967.
The motor vehicle has provided mobility and individual freedom for millions of people. However, vehicles embody the dilemma of contemporary industrialisation in that the environmental costs of automobility are equally large. This non-country specific study undertakes a PROMETHEE-based preference ranking of a small set of motor vehicles based on constituents of their exhaust emissions. As a model of an interested party's preference ranking of the motor vehicles, the subsequent uncertainty (sensitivity) analysis considered here, relates to what minimal (lean) changes would be necessary to a vehicle's emissions so that their preference ranking is improved. For a particular manufacturer, it can identify the necessary engineering performance modifications to be made to improve their perceived consumer based ranking. This is compounded by a further consideration of different levels of importance conferred on the criteria (vehicle emissions) and analogous analyses undertaken. The visual elucidation of the results rankings and changes to criteria values, offers a clear presentation of the findings to the interested parties.  相似文献   
968.
We demonstrate the asymptotic equivalence between commonly used test statistics for out‐of‐sample forecasting performance and conventional Wald statistics. This equivalence greatly simplifies the computational burden of calculating recursive out‐of‐sample test statistics and their critical values. For the case with nested models, we show that the limit distribution, which has previously been expressed through stochastic integrals, has a simple representation in terms of χ2‐distributed random variables and we derive its density. We also generalize the limit theory to cover local alternatives and characterize the power properties of the test.  相似文献   
969.
'Service user': regressive or liberatory terminology?   总被引:1,自引:1,他引:0  
The term 'service users' has come to be increasingly used both in the UK and beyond to describe people on the receiving end of health, welfare and social care policies and services, including disabled people. This use of language is contentious. It has come in for criticism as presenting people in passive, consumerist terms. However, many disabled people, and others, use the term of themselves. This article seeks to develop discussion about this terminology and suggests that as well as being used by state and service system in regressive and pejorative ways, it may also serve as a unifying concept which has helped groups to act with solidarity and to challenge and seek to improve their status in society. In this way, it may parallel the terms 'disabled' and 'disability' as used within social approaches to disability.  相似文献   
970.
Times have arguably never been better for minority nationalism. The hollowing out of the nation-state has provided spaces for minority nations to assert their identities and seek wider forms of self-rule. Their position is strengthened by the increased salience of development strategies at the regional scale that draw on the cooperation and coordination of economic actors. In this context, minority nationalism can help foster regional economic success by providing increased cohesion and cross-class collaboration. In return, regional economic success promises to strengthen the nation by providing resources to smooth over class divisions. This article lays out this argument, but raises a number of political and economic contradictions that threaten to interfere both with the construction of regional strategies, and with their ability to paper over class divisions within the nation. It concludes with a brief discussion of the Québec case to show how the promise of a mutually reinforcing relationship between minority nationalism and regional strategies runs up against a series of contradictions in practice.  相似文献   
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