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971.
Odds are generally defined as the number of successes divided by the number of failures in a given number of trials. An odds ratio is the ratio of one odds divided by another. Odds ratios can be adjusted to reflect associations with the outcome independently of the influence of associations with other variables. These are adjusted odds ratios. There are several well known methods for comparing odds ratios and testing for statistically significant differences between them. Analogous methods for adjusted odds ratios are not well known or well documented. One method for comparing adjusted odds ratios is explained by Hosmer and Lemeshow (Applied logistic regression, 2000). This method is used for the odds ratios for two variables from the same data set. The purpose of this analysis was to apply this method to a different situation: comparing odds ratios for the same variable from two different data sets. Monte Carlo trials were used to assess the performance of the method and these indicated the method performed well.  相似文献   
972.
A field study was conducted to test the effectiveness of intergroup contact (Allport, The nature of prejudice, 1954) as a predictor of explicit and implicit attitudes toward immigrants and to examine the processes driving its effects. Participants were Italian businessmen owning small and medium enterprises in Northern Italy who had daily contact with their immigrant workers. We tested a model in which contact ameliorated explicit attitudes, measured as support for social policies toward immigration, through reduced negative outgroup stereotypes. Furthermore, we predicted that contact would have a direct, unmediated effect on improved implicit attitudes toward immigrants, assessed with an Implicit Association Test (Greenwald et al., J Personal Soc Psychol 74:1464–1480, 1998). The results were fully consistent with predictions, thus providing strong support for the contact hypothesis at both an explicit and at an implicit level. The lack of correlation between explicit and implicit attitudes supports dual-process models, suggesting that the two types of attitudes are formed through different processes. The theoretical and practical implications of the findings are discussed.  相似文献   
973.
Due to the impact of knowledge-based economies, all countries strive to foster creative education. Research has demonstrated that creativity is influenced both by individual characteristics and by the environment. Previous research examining creative teaching by teachers in Taiwan has typically focused on the relationships between creative teaching and innovative personal characteristics, school leaders’ behaviors, and internal motivation. The purpose of this study was to move beyond prior research to investigate the relationship between creative teaching behaviors and innovation-fostering elements of the organizational climate in schools. In addition, we examined the impact on teacher creativity of urban versus rural school location.  相似文献   
974.
The intraday seasonal variance pattern contains stochastic as well as deterministic components. Therefore, the estimation of information arrivals in the associated volatility process requires the proper filtering of both of these seasonal components. However, popular current models remove only the deterministic part of the typical U‐shape volatility. Here, we provide the first empirical results of the importance of the stochastic component, as developed by Cho and Daigler (2012). We show that a highly significant additional 8.5% to 12.9% of the total seasonal variance is explained by the stochastic seasonal variance component for S&P500 futures, live cattle futures, and the Japanese yen‐U.S. dollar spot exchange rate. Moreover, we show that the stochastic seasonal filtering model implemented here does not create any statistical distortions of the filtered series, as occurs with deterministic‐based seasonal adjustment processes, as well as comparing the model examined here with the most popular current deterministic model. As part of our analysis we examine the application of the model to macroeconomic news and out‐of‐sample results for the model. © 2012 Wiley Periodicals, Inc. Jrl Fut Mark 34:479–495, 2014  相似文献   
975.
The persistence property of inflation is an important issue not only for economists, but especially for central banks, given that the degree of inflation persistence determines the extent to which central banks can control inflation. Further, not only is it the level of inflation persistence that is important in economic analyses, but also the question of whether the persistence varies over time, for instance, across business cycle phases, is equally pertinent, since assuming constant persistence across states of the economy is sure to lead to misguided policy decisions. Against this backdrop, we extend the literature on long-memory models of inflation persistence for the US economy over the monthly period of 1920:1–2014:5, by developing an autoregressive fractionally integrated moving-average-generalized autoregressive conditional heteroskedastic model with a time-varying memory coefficient which varies across expansions and recessions. In sum, we find that inflation persistence does vary across recessions and expansions, with it being significantly higher in the former than in the latter. As an aside, we also show that persistence of inflation volatility is higher during expansions than in recessions. Understandably, our results have important policy implications.  相似文献   
976.
The design of the tax system matters for economic growth. During times of economic crisis, tax instruments such as temporary tax cuts can be used to soften adverse effects on the economy by stimulating private and corporate spending. However, empirical evidence suggests that the overall impact of short term tax policies is limited. In the long run, the structure of the tax system is essential to building up an investment friendly and innovation-stimulating environment, which will promote sustainable economic growth.  相似文献   
977.
This paper begins with a statistical formulation of the Environmental Kuznets Curve (EKC) and discusses the major econometric problems raised in the literature in testing this hypothesis using panel data. A simple t‐test is then presented that avoids these econometric problems. The result from applying the t‐test confirms conclusively the EKC for CO2 as formulated.  相似文献   
978.
The answer to the question “What will future potential growth be?” is as important as it is unknowable. This paper attempts to predict future U.S. potential output growth by combining what is unknown (future productivity growth, the performance of the labor market) with what is known (the evolution of the age structure of the population). It does so in two ways. First, this paper uses the historical experience of potential labor productivity growth, labor force participation, and weekly hours to simulate a range of outcomes for future potential growth—finding a 90% confidence interval that ranges from 0.7% annual growth to 3.0% annual growth, centered by construction around the Congressional Budget Office projection of 1.8% annual growth. Second, the paper examines a range of specific economic policies that the Trump Administration might pursue in terms of their impact on economic growth both in the short run and over the next decade—finding that an outer bound of these policies could be plus or minus 0.5 percentage point on the annual growth rate, but that these policies would most likely subtract a small amount from growth.  相似文献   
979.
980.
The aim of this paper is to analyse the phenomenon of crowdfunding and determine whether it can be considered a service ecosystem, where the context frames innovation through value co-creation. A qualitative, multiple case study approach is used to analyse three platforms and six initiatives in the Spanish arts sector. The findings reveal that crowdfunding can be considered an ecosystem where value-in-context frames seven types of value co-creation, offering a contribution both to ecosystem theory and to the field of co-creation.  相似文献   
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