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971.
Annette Pascual-Marrero Ediel O. Ramos-Meléndez José E. Morales-Quiñones Pablo Rodríguez-Ortiz 《International journal of injury control and safety promotion》2018,25(1):14-22
This study aimed to describe the distribution of injury mechanisms and to assess the impact of those mechanisms on the morbidity and mortality of trauma. All patients admitted to Puerto Rico Trauma Hospital (2002–2011) for road-traffic collisions (RTCs, 5,371), gunshot wounds (GSWs, 2,946), falls (2,319), pedestrian accidents (1,652), and stab wounds (SWs, 1,073) were selected. Gunshot victims were 1.19 (95%CI: 1.07–1.33) times as likely as road-traffic victims to have an ISS ≥25. Pedestrians were 1.76 (95%CI: 1.49–2.09) times more likely to have a GCS ≤8 than road-traffic victims were. The risk of dying was 2.64 (95%CI: 2.20–3.16) times higher for gunshot victims and 1.51 (95%CI: 1.23–1.86) times higher for pedestrians compared to patients who had had RTCs. Gunshot victims and pedestrians had the worst clinical outcomes. Accordingly, these patients should receive the most aggressive clinical management. Furthermore, it is imperative to develop public health campaigns on trauma prevention. 相似文献
972.
973.
In the last three decades, a variety of stochastic reserving models have been proposed in the general insurance literature mainly using (or reproducing) the well-known Chain-Ladder claims-reserving estimates. In practice, when the data do not satisfy the Chain-Ladder assumptions, high prediction errors might occur. Thus, in this article, a combined methodology is proposed based on the stochastic vector projection method and uses the regression through the origin approach of Murphy, but with heteroscedastic errors instead, and different from those that used by Mack. Furthermore, the Mack distribution-free model appears to have higher prediction errors when compared with the proposed one, particularly, for data sets with increasing (regular) trends. Finally, three empirical examples with irregular and regular data sets illustrate the theoretical findings, and the concepts of best estimate and risk margin are reported. 相似文献
974.
Two-part models based on generalized linear models are widely used in insurance rate-making for predicting the expected loss. This paper explores an alternative method based on quantile regression which provides more information about the loss distribution and can be also used for insurance underwriting. Quantile regression allows estimating the aggregate claim cost quantiles of a policy given a number of covariates. To do so, a first stage is required, which involves fitting a logistic regression to estimate, for every policy, the probability of submitting at least one claim. The proposed methodology is illustrated using a portfolio of car insurance policies. This application shows that the results of the quantile regression are highly dependent on the claim probability estimates. The paper also examines an application of quantile regression to premium safety loading calculation, the so-called Quantile Premium Principle (QPP). We propose a premium calculation based on quantile regression which inherits the good properties of the quantiles. Using the same insurance portfolio data-set, we find that the QPP captures the riskiness of the policies better than the expected value premium principle. 相似文献
975.
Nathalia Suchek Cristina I. Fernandes Sascha Kraus Matthias Filser Helena Sjögrén 《Business Strategy and the Environment》2021,30(8):3686-3702
The circular economy emerged as an alternative model to the linear system, which now appears to be reaching its physical limitations. To transition to a circular economy, companies must not only be aware of but also engage in more sustainable practices. For such a transition, companies must rethink and innovate their business models and the ways they propose value to their clients while simultaneously considering environmental and social facets. This systematic literature review sought to map out from the company perspective the key topics interrelated with innovation and the circular economy, describing the internal and external factors to consider in such transition processes. Key lines of research were identified, and suggestions for future research and for facilitating movement toward a circular economy are provided. This work contributes to deepening the literature by identifying the priority areas concerning the circular economy and encouraging future research that meets international standards of excellence. 相似文献
976.
Mera Valentina-Ioana Silaghi Monica Ioana Pop Turcu Camélia 《Open Economies Review》2020,31(2):343-369
Open Economies Review - This paper aims at building a money demand function that takes account of the heterogeneities of the Central and Eastern European Countries (CEECs) in the context of the... 相似文献
977.
Leonardo Aureliano-Silva Carlos Alberto Alves Sérgio Luiz do Amaral Moretti 《食品市场学杂志》2019,25(3):322-339
This study analyzes the effect of informational clues and Chef-Cuisine congruence, and their relation to advertisements for a Japanese restaurant. Two experiments were conducted with 171 consumers. Findings supported the following: Congruence between a Japanese restaurant and Japanese Chef results in higher approval ratings than the combination of Japanese restaurant with Brazilian Chef. However, if the advertisement states that the restaurant has won an award, then Chef-restaurant congruence is no longer an important factor in consumers’ evaluations. 相似文献
978.
We model endogenous catastrophic risk in a new way. We call it “inertia risk”, which accounts for delays between physical variables and the hazard rate – a characteristic often observed in reality. The added realism significantly affects optimal policies relative to the standard model of catastrophic risk. The probability of a catastrophe occurring at some point in time can span the entire interval [0,1], and is not 0 or 1 as is typical in standard models. Inertia risk can also generate path dependences. We illustrate the implications for policy in a simple model of climate change. 相似文献
979.
Francisco Liébana-Cabanillas Francisco Muñoz-Leiva J. Sánchez-Fernández 《Service Business》2018,12(1):25-64
Mobile devices and social media have led to a profound revolution of modern society, obliging many companies to reorient their sales systems towards more successful commercial formats (mobile commerce and social commerce). The mobile payment, for instance, as an emerging and supplementary service to these new commercial formats, is now undergoing the adoption process. Mobile payment has long been discussed, but it has not yet reached the usage levels expected by the different mass market players (financial institutions, telephone operators, etc.) in Western societies. The purpose of this paper is to analyze users’ acceptance of mobile payment systems on social networks. In order to explain acceptance, we have integrated trust and perceived risk into the traditional TAM model. To complete this study, we have established the decisive factors of this payment system by analyzing user’s gender, age and experience level. The study was conducted through an online survey among a national panel composed by 2.012 social network users. The results of this research support previous studies and provide alternatives for companies to consolidate this new business model by means of the new technical developments. 相似文献
980.
José-María Montero Tiziana Laureti Román Mínguez Gema Fernández-Avilés 《Review of Income and Wealth》2020,66(3):512-533
This paper focuses on a new strand of research that uses stochastic approach for making spatial price comparisons. We propose a novel method to account for the presence of spatial dependencies in consumer prices and consequently in price indexes by imposing penalization conditions on the estimation of traditional CPD models leading to the spatially-penalized country-product-dummy (SP-CPD) model. The paper proposes an appropriate estimation strategy, which enables us to simultaneously estimate all the parameters in the model, including the smoothing parameter of the penalization term instead of determining it externally. In order to estimate spatial price indexes for areas lacking in price data, we suggest applying the kriging methodology to the price indexes obtained from the SP-CPD model. This new approach is applied to official Italian CPI data for constructing regional spatial price indexes for 2014. The results show that price levels are higher in the Northern-Central regions than in the South. 相似文献