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171.
There is considerable disagreement in academic scholarship and beyond as to whether, in cases of bad reputations, companies will want to communicate corporate social responsibility (CSR) activities because this kind of communication is likely to increase consumers’ skepticism. In this regard, the two empirical studies discussed in this article examine the influence of prior company reputation on consumers’ trust in response to CSR communication in general and the development in response to continuous CSR activities and their ongoing communication by companies as well as by the media in particular. The two studies show that consumers’ trust in companies’ CSR activities increases after a second presentation of information by companies even in instances when companies had prior negative reputations. The second study in particular fills a gap in the literature on underlying mechanisms of consumers’ reactions to CSR communication. The results suggest that companies with prior negative reputations do not need to remain silent about their CSR activities; instead, CSR communication can help improve consumers’ trust in companies. However, the findings of these two studies also suggest that this positive development is short-lived. Consumers’ developing trust in companies’ CSR activities decreases significantly if they are exposed to negative information on these companies.  相似文献   
172.
基于价值链视角,构建涵盖人才资源在区域空间层面集聚生成、地区配置、效能产出3个维度在内的区域人才集聚水平评价指标体系,采用专家咨询AHP-信息熵组合赋权法构建综合评价模型和耦合协调度模型,对2010—2018年长江经济带沿线省市人才集聚水平进行测度与时空演化特征分析。结果表明,就长江经济带整体而言,考察期内地区人才集聚水平总体呈现逐年上升态势,但仍处于低水平状态;沿线省市人才集聚水平差异显著,缩小趋势渐缓,整体呈现局部高水平、全局低效率的不利境况;各省市人才集聚水平关键维度的耦合协调度整体呈显著波动递增态势,但内部耦合协调度存在不平衡发展问题,影响地区人才集聚水平整体提升。为提升长江经济带人才集聚水平,推进沿线地区协调发展,需强化区域人才合作机制,采取差别化精准策略破解沿线地区人才集聚低水平、不协调的短板因素。  相似文献   
173.
The main objective of the M5 competition, which focused on forecasting the hierarchical unit sales of Walmart, was to evaluate the accuracy and uncertainty of forecasting methods in the field to identify best practices and highlight their practical implications. However, can the findings of the M5 competition be generalized and exploited by retail firms to better support their decisions and operation? This depends on the extent to which M5 data is sufficiently similar to unit sales data of retailers operating in different regions selling different product types and considering different marketing strategies. To answer this question, we analyze the characteristics of the M5 time series and compare them with those of two grocery retailers, namely Corporación Favorita and a major Greek supermarket chain, using feature spaces. Our results suggest only minor discrepancies between the examined data sets, supporting the representativeness of the M5 data.  相似文献   
174.
Edouard Wemy 《Applied economics》2019,51(43):4711-4725
Several studies argue that the recent decline in the secular trend of the labour income share is mostly driven by capital-embodied technological progress which is typically identified with trend reductions in the relative price of investment. In this paper, I use data from the United States to assess the nature of the relationship between trends in the labour share and the relative price of investment. Results from co-integration tests reveal that the share and the relative price of investment are most likely not co-integrated. However, co-variation tests indicate that both time series share a common stochastic component, and additional tests of structural breaks point at the presence of a common change in the mean or trend of both series. These results suggest that capital-embodied or investment-specific technological progress may have played an important role in the decline of the secular trend of the labour share.  相似文献   
175.
Wind power forecasts with lead times of up to a few hours are essential to the optimal and economical operation of power systems and markets. Vector autoregression (VAR) is a framework that has been shown to be well suited to predicting for several wind farms simultaneously by considering the spatio-temporal dependencies in their time series. Lasso penalisation yields sparse models and can avoid overfitting the large numbers of coefficients in higher dimensional settings. However, estimation in VAR models usually does not account for changes in the spatio-temporal wind power dynamics that are related to factors such as seasons or wind farm setup changes, for example. This paper tackles this problem by proposing a time-adaptive lasso estimator and an efficient coordinate descent algorithm for updating the VAR model parameters recursively online. The approach shows good abilities to track changes in the multivariate time series dynamics on simulated data. Furthermore, in two case studies it shows clearly better predictive performances than the non-adaptive lasso VAR and univariate autoregression.  相似文献   
176.
Accurate probabilistic forecasting of wind power output is critical to maximizing network integration of this clean energy source. There is a large literature on temporal modeling of wind power forecasting, but considerably less work combining spatial dependence into the forecasting framework. Through the careful consideration of the temporal modeling component, complemented by support vector regression of the temporal model residuals, this work demonstrates that a DVINE copula model most accurately represents the residual spatial dependence. Additionally, this work proposes a complete set of validation mechanisms for multi-h-step forecasts that, when considered together, comprehensively evaluate accuracy. The model and validation mechanisms are demonstrated in two case studies, totaling ten wind farms in the Texas electric grid. The proposed method outperforms baseline and competitive models, with an average Continuous Ranked Probability Score of less than 0.15 for individual farms, and an average Energy Score of less than 0.35 for multiple farms, over the 24-hour-ahead horizon. Results show the model’s ability to replicate the power output dynamics through calibrated and sharp predictive densities.  相似文献   
177.
The objective of the paper is to determine if the futures prices of hard red spring wheat (HRSW) have stabilizing or destabilizing impact on spot HRSW price in North America. Several important results emerge from thorough empirical analysis. First, both Granger causality tests and directed acyclic graph algorithms (DAGs) point to two-way causality between futures and spot HRSW prices and thus endogeneity in both prices formation. To the contrary, both procedures suggest that ending stocks are exogenous to spot and futures HRSW prices. Both vector error correction model and impulse response functions point to a large and long-lasting impact of a shock to futures price on spot price level. Finally, variance decomposition analysis indicates that futures prices are responsible for the bulk of spot price volatility in both short and long run. Our result is consistent with those of theoretical models suggesting that when production (supply side) is the dominant disturbance, spot price is destabilized in both the short and the long run by futures prices. An important implication of this research is the need for alternative market mechanisms or alternative farm policy measures that would mitigate price risk and ensure sustainable farming of American HRSW farmers.  相似文献   
178.
This paper estimates a three-frequency dynamic factor model for nowcasting the Canadian provincial gross domestic product (GDP). The Canadian provincial GDP at market prices is released by Statistics Canada annually with a significant lag (11 months). This necessitates a mixed-frequency approach that can process timely monthly data, the quarterly national accounts, and the annual target variable. The model is estimated on a wide set of provincial, national and international data. In a pseudo real-time exercise, we find that the model outperforms simple benchmarks and is competitive with more sophisticated mixed-frequency approaches (MIDAS models). We also find that variables from the Labour Force Survey are important predictors of real activity. This paper expands previous work that has documented the importance of foreign variables for nowcasting Canadian GDP. This paper finds that including national and foreign predictors is useful for Ontario, while worsening the nowcast performance for smaller provinces.  相似文献   
179.
We introduce a class of semiparametric time series models (SemiParTS) driven by a latent factor process. The proposed SemiParTS class is flexible because, given the latent process, only the conditional mean and variance of the time series are specified. These are the primary features of SemiParTS: (i) no parametric form is assumed for the conditional distribution of the time series given the latent process; (ii) it is suitable for a wide range of data: non-negative, count, bounded, binary, and real-valued time series; (iii) it does not constrain the dispersion parameter to be known. The quasi-likelihood inference is employed in order to estimate the parameters in the mean function. Here, we derive explicit expressions for the marginal moments and for the autocorrelation function of the time series process so that a method of moments can be employed to estimate the dispersion parameter and also the parameters related to the latent process. Simulated results that aim to check the proposed estimation procedure are presented. Forecasting procedures are proposed and evaluated in simulated and real data. Analyses of the number of admissions in a hospital due to asthma and a total insolation time series illustrate the potential for practical situations that involve the proposed models.  相似文献   
180.
Given many nonprofit service organisations rely on volunteers to provide valued services to their communities, examining the factors that impact the retention and recruitment of volunteers is of central importance for the success and longevity of many community-based services. Psychological ownership is a phenomenon whereby objects that are not physically or legally possessed can be the target of ownership feelings. While such psychological ownership has been examined in the paid-employment literature as an antecedent for prosocial behaviours, there has been no examination of psychological ownership within the volunteering literature. As such, this paper examines the role of psychological ownership as a factor in volunteer retention for predominantly community-based nonprofit service organisations by examining how the sense of ownership over the nonprofit service provider affects volunteering attitudes and intentions. Alongside ownership, previous volunteering behaviours, and time pressures are also examined as contributing factors. Results indicate that volunteering does increase ownership perceptions, and those ownership perceptions have positive outcomes for volunteering behaviours. However, time pressure is a significant moderator of these relationships and different volunteering behaviours can be observed for high and low time-pressured volunteers.  相似文献   
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