题目：巴基斯坦交通部门的能源替代效应：超越对数生产函数方法(Energy substitution effect on transport sector of Pakistan: A trans-log production function approach)

作者：林伯强*，Muhammad Yousaf Raza

期刊：清洁生产(Journal of Cleaner Production)

详细：251卷，2期，2020年4月

DOI：https://doi.org/10.1016/j.jclepro.2019.119606

文献导读：

交通运输在当今社会发挥着积极作用，交通运输部门的能源消费在总消费中占重要份额。公路、铁路、公路、航运和航空直接或间接地与一个经济体的所有重要部门联系在一起。然而，由于车辆所产生的废气排放，运输部门的二氧化碳（CO₂）排放量迅速上升。

巴基斯坦的交通运输部门是一个重要部门，对巴基斯坦国内生产总值（GDP）的贡献率为13.04%，就业率占6%。但交通部门也是巴基斯坦的高能耗和高CO₂排放部门。在巴基斯坦交通运输业的不同类型中，公路运输被认为是巴基斯坦交通运输业的强项。由于人口的不断增长，在过去十年中，汽车数量在2018年增加了83.1万辆和341万辆。根据巴基斯坦交通运输业过去和现在的情况，本文对巴基斯坦交通运输业的发展趋势作了初步判断：巴基斯坦交通运输业中的化石燃料可能长期保持低增长。

因此，研究巴基斯坦交通部门要素投入的替代效应具有重要的实际意义。基于1991-2018年运输部门数据，采用超越对数生产函数和岭回归方法，本文分析了巴基斯坦交通部门能源、资本和劳动之间的替代效应。相比于以往的研究，本文包括了新的交通部门数据（即出租车、私人出租车公司、地铁公交系统、橙色列车），并考虑了与巴基斯坦国家气候变化政策（NCCP）相关的交通碳排放政策。

Abstract:

Transport sector of Pakistan is one of the highest fossil fuel consumption and carbon dioxide (CO₂) emission sector. As a key user of fossil fuel energy, Pakistan's transport sector has created many problems i.e. noise, air pollution, CO₂ emissions and environmental problem. In this study, trans-log production function model for Pakistan's transport sector is established and input factors of labor, capital, and energy consumption are comprised. The output elasticity of an individual, input elasticity between a pair of factors, and elasticity of substitution between input factors are analyzed. To manage the multicollinearity issue, ridge regression is applied at different values of K. From 1991 to 2018, the outcomes show that output elasticities and a pair of input factor's elasticities are increasing. The elasticities of substitutions between labor-energy consumption and capital-energy consumption show higher outcomes because of the more elevated amount of substitution elasticities. The substitution elasticity between labor and capital starts from 0.9797 to 0.9326 with slightly decreasing trend. The outcomes suggest that maximum output can be achieved by increasing capital and energy technologies. By allocating the maximum capital in the transport industry, energy-saving technologies, substitution between energy and capital, and substitution among capital-labor can enhance environmental protection. In the above's view function, the present study estimates the level of energy-saving and CO₂ emissions reduction under the different scenarios from 2015 to 2018. The policy suggestions of the results are given below.

Keywords: Transport industry; Trans-log production function; Elasticity of substitution;

Pakistan