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81.
We develop an equilibrium endowment economy with Epstein-Zin recursive utility and a Lévy time-change subordinator, which represents a clock that connects business and calendar time. Our setup provides a tractable equilibrium framework for pricing non-Gaussian jump-like risks induced by the time-change, with closed-form solutions for asset prices. Persistence of the time-change shocks leads to predictability of consumption and dividends and time-variation in asset prices and risk premia in calendar time. In numerical calibrations, we show that the risk compensation for Lévy risks accounts for about one-third of the overall equity premium. 相似文献
82.
Forecast combinations of computational intelligence and linear models for the NN5 time series forecasting competition 总被引:1,自引:0,他引:1
Robert R. AndrawisAuthor Vitae Hisham El-ShishinyAuthor Vitae 《International Journal of Forecasting》2011,27(3):672
In this work we introduce the forecasting model with which we participated in the NN5 forecasting competition (the forecasting of 111 time series representing daily cash withdrawal amounts at ATM machines). The main idea of this model is to utilize the concept of forecast combination, which has proven to be an effective methodology in the forecasting literature. In the proposed system we attempted to follow a principled approach, and make use of some of the guidelines and concepts that are known in the forecasting literature to lead to superior performance. For example, we considered various previous comparison studies and time series competitions as guidance in determining which individual forecasting models to test (for possible inclusion in the forecast combination system). The final model ended up consisting of neural networks, Gaussian process regression, and linear models, combined by simple average. We also paid extra attention to the seasonality aspect, decomposing the seasonality into weekly (which is the strongest one), day of the month, and month of the year seasonality. 相似文献
83.
Reza EbrahimpourAuthor Vitae Hossein NikooAuthor VitaeSaeed MasoudniaAuthor Vitae Mohammad Reza YousefiAuthor VitaeMohammad Sajjad GhaemiAuthor Vitae 《International Journal of Forecasting》2011,27(3):804
A new method for forecasting the trend of time series, based on mixture of MLP experts, is presented. In this paper, three neural network combining methods and an Adaptive Network-Based Fuzzy Inference System (ANFIS) are applied to trend forecasting in the Tehran stock exchange. There are two experiments in this study. In experiment I, the time series data are the Kharg petrochemical company’s daily closing prices on the Tehran stock exchange. In this case study, which considers different schemes for forecasting the trend of the time series, the recognition rates are 75.97%, 77.13% and 81.64% for stacked generalization, modified stacked generalization and ANFIS, respectively. Using the mixture of MLP experts (ME) scheme, the recognition rate is strongly increased to 86.35%. A gain and loss analysis is also used, showing the relative forecasting success of the ME method with and without rejection criteria, compared to a simple buy and hold approach. In experiment II, the time series data are the daily closing prices of 37 companies on the Tehran stock exchange. This experiment is conducted to verify the results of experiment I and to show the efficiency of the ME method compared to stacked generalization, modified stacked generalization and ANFIS. 相似文献
84.
This paper is a re-examination of the benefits and limitations of decomposition and combination techniques in the area of forecasting, and also a contribution to the field, offering a new forecasting method. The new method is based on the disaggregation of time series components through the STL decomposition procedure, the extrapolation of linear combinations of the disaggregated sub-series, and the reaggregation of the extrapolations to obtain estimates for the global series. Applying the forecasting method to data from the NN3 and M1 Competition series, the results suggest that it can perform well relative to four other standard statistical techniques from the literature, namely the ARIMA, Theta, Holt-Winters’ and Holt’s Damped Trend methods. The relative advantages of the new method are then investigated further relative to a simple combination of the four statistical methods and a Classical Decomposition forecasting method. The strength of the method lies in its ability to predict long lead times with relatively high levels of accuracy, and to perform consistently well for a wide range of time series, irrespective of the characteristics, underlying structure and level of noise of the data. 相似文献
85.
Alwin HaenselAuthor Vitae Ger KooleAuthor Vitae 《International Journal of Forecasting》2011,27(3):942
A highly accurate demand forecast is fundamental to the success of every revenue management model. As is often required in both practice and theory, we aim to forecast the accumulated booking curve, as well as the number of reservations expected for each day in the booking horizon. To reduce the dimensionality of this problem, we apply singular value decomposition to the historical booking profiles. The forecast of the remaining part of the booking horizon is dynamically adjusted to the earlier observations using the penalized least squares and historical proportion methods. Our proposed updating procedure considers the correlation and dynamics of bookings both within the booking horizon and between successive product instances. The approach is tested on real hotel reservation data and shows a significant improvement in forecast accuracy. 相似文献
86.
基于时间距离的河南城市经济联系及其空间结构 总被引:1,自引:0,他引:1
采用GIS网络分析获得城市间公路交通的OD时间距离对引力模型的距离进行修正,对河南各地市间1997年和2007年的经济联系进行测算和比较,继而采用分形模型对各城市对外经济联系总量及联系强度的分形维数进行测算,探讨了地市对外经济联系的空间结构特征.研究表明,河南各城市经济联系总量等级特征明显,地市间经济联系初步形成了“十... 相似文献
87.
We use ARCH time series models to derive model based prediction intervals for the Total Fertility Rate (TFR) in Norway, Sweden, Finland, and Denmark up to 2050. For the short term (5–10 yrs), expected TFR‐errors are compared with empirical forecast errors observed in historical population forecasts prepared by the statistical agencies in these countries since 1969. Medium‐term and long‐term (up to 50 years) errors are compared with error patterns based on so‐called naïve forecasts, i.e. forecasts that assume that recently observed TFR‐levels also apply for the future. 相似文献
88.
刘振英 《山西经济管理干部学院学报》2003,11(4):34-35
阐述了施工工期与造价的辩证关系。即:工期与经济效益的关系;工期与自然损耗的关系;工期与固定成本的关系;工期与投资成本的关系。 相似文献
89.
Dale B. Tuttle 《Scandinavian Journal of Management》1997,13(4):349-366
This paper develops a classification system of temporal orientations in an effort to provide processual researchers with a framework for understanding the potential impact of temporal orientations on processual research methods and findings. In developing the classification system four general conceptions of time are reviewed, including physiological, objective, psychological, and socially constructed relative time. Specific dimensions of temporal orientation previously studied are identified, and additional dimensions are offered. It is suggested that temporal concerns are endemic to management and organizational processes, and that differences in temporal orientations among researchers and organizational informants should be considered when conducting processual research. 相似文献
90.
Luca Lambertini 《Journal of Evolutionary Economics》2005,15(4):443-465
I propose a dynamic duopoly model where firms enter simultaneously but compete hierarchically á la Stackelberg at each instant over time. They accumulate capacity through costly investment, with capital accumulation dynamics being affected by an additive shock the mean and variance of which are known. The main findings are the following. First, the Stackelberg game is uncontrollable by the leader; hence, it is time consistent. Second, the leader invests more than the follower; as a result, in the steady state, the leader’s capacity and profits are larger than the follower’s. Therefore, the present analysis does not confirm Gibrat’s Law, since the individual growth rate is determined by the timing of moves.JEL Classification:
C61, C73, D43, D92, L13Financial support within the project The post-entry performance of firms: technology, growth and survival lead by Enrico Santarelli, co-financed by the University of Bologna and MIUR, is gratefully acknowledged. I thank Uwe Cantner, Roberto Cellini, Roberto Golinelli, Helen Louri, Enrico Santarelli, Antonello Scurcu, Peter Thompson, two anonymous referees and the audience at the final workshop of the project (Bologna, November 22-23, 2002) for useful comments and discussion. The usual disclaimer applies. 相似文献