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991.
992.
Studies have demonstrated the inadequacy of relying on existing administrative boundaries or simple proximity to define an affected community. The proposal and siting of hazardous facilities can have a range of impacts upon people across wide areas, with some more affected than others as a result of living with the physical impacts of construction or the fear associated with perceived risk. We term those most affected the directly affected population and propose a two-stage model for identifying an affected community which places those most affected at the centre of the definition. The second stage is to identify the relationships those most affected have with the wider elements of the sense of community to discover the existing community or communities which are affected. Illustrated by the siting of a low-level radioactive waste disposal facility at Dounrey in the north of Scotland, we show that elements of the lived community experience may have very different shapes, extents and conflicting interests which pose challenges for their incorporation into a siting process. The two-stage model presented in this paper, by placing those most directly affected at the centre and working from there out into the existing communities, identifies issues early in any siting process to improve their incorporation and amelioration. 相似文献
993.
Predictive models of health care costs have become mainstream in much health care actuarial work. The Affordable Care Act requires the use of predictive modeling-based risk-adjuster models to transfer revenue between different health exchange participants. Although the predictive accuracy of these models has been investigated in a number of studies, the accuracy and use of models for applications other than risk adjustment have not been the subject of much investigation. We investigate predictive modeling of future health care costs using several statistical techniques. Our analysis was performed based on a dataset of 30,000 insureds containing claims information from two contiguous years. The dataset contains more than 100 covariates for each insured, including detailed breakdown of past costs and causes encoded via coexisting condition flags. We discuss statistical models for the relationship between next-year costs and medical and cost information to predict the mean and quantiles of future cost, ranking risks and identifying most predictive covariates. A comparison of multiple models is presented, including (in addition to the traditional linear regression model underlying risk adjusters) Lasso GLM, multivariate adaptive regression splines, random forests, decision trees, and boosted trees. A detailed performance analysis shows that the traditional regression approach does not perform well and that more accurate models are possible. 相似文献
994.
Saku J. Mäkinen Juho Kanniainen Ilkka Peltola 《Journal of Product Innovation Management》2014,31(3):451-465
Planning new product development (NPD) activities is becoming increasingly difficult, as contemporary businesses compete at the level of business ecosystems in addition to the firm‐level product‐market competition. These business ecosystems are built around platforms interlinking suppliers, complementors, distributors, developers, etc. together. The competitiveness of these ecosystems relies on members utilizing the shared platform for their own performance improvement, especially in terms of developing new valuable offerings for end users. Therefore, managing the development of the platform‐based applications and gaining timely end‐user input for NPD are of vital importance both to the ecosystem as a whole and to the developers. Subsequently, to succeed in NPD planning developers utilizing beta testing need a thorough understanding of the adoption dynamics of beta products. Developers need to plan for example resource allocation; development costs; and timing of commercial, end‐product launches. Therefore, the anticipation of the adoption dynamics of beta products emerges as an important antecedent in planning NPD activities when beta testing is used for gaining end‐user input to the NPD process. Consequently, we investigate how free beta software products that are built upon software platforms diffuse among their end users in a cocreation community. We specifically study whether the adoption of these beta products follows Bass or Gompertz model dynamics used in the previous literature when modeling the adoption of stand‐alone products. Further, we also investigate the forecasting abilities of these two models. Our results show that the adoption dynamics of free beta products in a cocreation community follow Gompertz's model rather than the Bass model. Additionally, we find that the Gompertz model performs better than the Bass model in forecasting both short and long out‐of‐sample time periods. We further discuss the managerial and research implications of our study. 相似文献
995.
996.
Xu Li 《Review of Quantitative Finance and Accounting》2011,37(1):87-104
The main purpose of this paper is to provide additional evidence about the effect of discretionary current accruals on the
pricing of IPOs. This paper seeks to discriminate between two alternative explanations for the prior findings: (1) behavioral
biases coupled with limited arbitrage; and (2) the sample- and period-specific nature of the results in the prior literature.
The IPOs from 1962 to 1998 were used to obtain the following results. First, there was not a negative association observed
between discretionary current accruals and subsequent price performance for the 1926–1971 period. Second, analysis reveals
that the pattern of cross-sectional evidence is inconsistent with the predictions made by behavioral theories. Third, in the
1972–1998 period, evidence of predictable negative performance attributable to IPO discretionary current accruals is limited
to NASDAQ firms. These findings are difficult to reconcile with the explanation of behavioral biases coupled with limited
arbitrage. 相似文献
997.
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
998.
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
999.
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
1000.
Global value chains (GVCs), led by transnational corporations (TNCs), have reshaped the world division of labor over the past two decades. GVCs are pervasive in low technology manufacturing, such as textile and apparel, as well as in more advanced industries like automobiles, electronics, and machines. This hierarchical division of labor generates wild competition at the lower value-added stages of production, where low wages and low profit margins prevail for workers and contract manufacturers in developing countries. At the top of the hierarchy another kind of competition prevails, centered on the ability to monitor and control intellectual property rights related to innovation, finance, and marketing. We argue that GVCs have had crucial effects on income inequality and the appropriation of rents in modern capitalism. 相似文献