中国沿海港口分层效率研究

为对处在不同效率层次的港口制定针对性决策,运用2014—2018年港口群的100个样本数据构建分层SBM-BPNN模型,该模型是基于松弛变量的测量(slack-based measure,SBM)模型与反向传播神经网络(back propagation neural network,BPNN)模型的结合。用构建的模型对2019年的港口群进行效率分层和决策制定。结果表明:分层SBM-BPNN模型不仅可以基于全体决策单元信息对分层SBM模型起替代作用,还可以在信息无法在各港口实时共享时,依据单个港口的信息对港口进行效率层次定位和分层最优决策的制定。分层效率研究有利于港口根据实际资源配置情况制定可行性较高的分阶段决策。

A New Approach for Ranking Efficient Units in Data Envelopment Analysis and Application to a Sample of Vietnamese Agricultural Bank Branches

This paper proposes a new approach for ranking efficiency units in data envelopment analysis as a modification of the super-efficiency models developed by Tone [1]. The new approach based on slacks-based measure of efficiency (SBM) for dealing with objective function used to classify all of the decision-making units allows the ranking of all inefficient DMUs and overcomes the disadvantages of infeasibility. This method also is applied to rank super-efficient scores for the sample of 145 agricultural bank branches in Viet Nam during 2007-2010. We then compare the estimated results from the new SCI model and the exsisting SBM model by using some statistical tests.

Super Efficiency and Misallocation: Evidence from Vietnamese Electric-Computer Industry

Misallocation means that the source is not distributed efficiently. This leads to an important question of how the relationship between misallocation and efficiency is (see [1]). The purpose of this study is to address the empirical relationship between misallocation and efficiency in the electric and computer industry in Vietnam during the 2005-2015 periods. To do this, we built a model that allowed us to evaluate the impact of misallocation and other factors on efficiency. The slack-based measured efficiency (SBM) model (Tone [2]), and the super-efficient model (Tone [3]) are used to estimate the firms’ efficiency. The approach of Hsieh and Klenow [4] is used to measure misallocation in the study area. Estimated results of the model about the relationship between misallocation and efficiency show that the variable representing the misallocation has a negative sign and statistical significance in all models. In other words, the misallocation negatively affects efficiency. The bigger the misallocation, the lower the efficiency.

中国省域绿色创新效率测度、差异分析及影响因素

绿色创新作为绿色发展和创新驱动战略的结合点,已成为全国绿色转型发展的重要战略目标。基于非期望产出的超效率SBM(slack-based measure)模型,对2012—2021年中国省域绿色创新效率测度评价,结合Dagum基尼系数对绿色创新效率进行差异分析,最后使用Tobit回归模型进行影响因素分析。研究结果表明:中国整体的绿色创新效率逐渐提高,但总的基尼系数呈现“W”型趋势,经济发展水平、市场竞争强度、对外开发水平和政府扶持力度均可显著提高绿色创新效率。根据研究结果,为提升绿色创新效率、缩小地区差异性提出对策建议。