人力资本推动中国加工贸易升级了吗?
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摘要
加工贸易转型升级是中国转变发展方式和改革开放战略的重要内容。本文以"大学扩招"政策的实施作为准自然实验,采用倍差法系统地评估了人力资本对中国加工贸易企业升级的影响及其作用机制。本文发现,人力资本扩张显著提高了加工贸易企业的出口技术复杂度,有利于促进加工贸易企业升级。渠道检验表明,人力资本扩张不仅促使了加工贸易企业加大研发投入和在职培训的力度,而且还促进了加工贸易企业进口使用更多种类和更高质量的中间投入品,同时还激励了加工贸易企业增加固定资产投资,这些因素共同推动了加工贸易企业升级。异质性分析发现,人力资本扩张对融资约束程度低、管理效率高、资本密集型以及外资型加工贸易企业升级的促进效应更大。此外,本文从更多的维度研究了人力资本与加工贸易升级的关系,发现人力资本扩张促进了加工贸易企业组织方式从来料加工向进料加工的转变,提高了加工贸易企业的出口国内附加值率,同时还提升了加工贸易企业的生产效率与自主创新能力。
Since the reform and opening up, Chinese processing trade has developed rapidly. However, most of it remains in the stage of OEM production, lacking self-owned brands and core technologies, and its export expansion is mainly driven by a large number of low-value-added primary processed goods. Problems persist, such as an insufficient ability to conduct independent research and development and a low ability to acquire added value; hence, Chinese processing trade is located in the middle and low end of the global value chain. In the context of the new type of international division of labor, it is urgent for Chinese processing trade to transform and upgrade. This paper treats the sharp increase in human capital resulting from the higher education reform as a quasi-natural experiment and adopts a difference-in-differences method to empirically investigate the impact of human capital expansion on the upgrading of Chinese processing trade. Based on Chinese firm-level data from 2000 to 2013, the results show that human capital expansion significantly raises processing firms' export technological sophistication and thus promotes the upgrading of Chinese processing firms. The mechanism tests show that human capital expansion not only spurs processing firms to increase R&D and on-the-job training expenditures but also inspires processing firms to import and use more varieties and higher quality intermediate inputs. It also encourages processing firms to increase fixed investments. All of these factors jointly promote the upgrading of processing firms. Further heterogeneity analysis shows that the positive effect of human capital expansion is larger for processing firms with lower financing constraints, higher management efficiency, higher capital intensity, and foreign-owned processing firms. We also document heterogeneity in the impact of human capital expansion on the upgrading of processing firms across fields. Finally, this paper explores the relationship between human capital and the upgrading of processing firms from additional perspectives and finds that human capital expansion tends to promote the transformation of the organization mode from pure assembly processing trade to import-and-assembly processing trade, increase processing firms' domestic value added ratio, and increase processing firms' production efficiency and independent innovation ability. This paper has important policy implications. The government should continue to attach great importance to and actively promote the development of higher education and realize the transformation from "scale expansion" to "quality improvement",thereby continuously improving the quality of human capital in China. Processing trade firms should hire and absorb high quality human capital at all costs, increase funding for on-the-job training, and raise the human capital of current employees. This paper makes the following contributions. First, it is one of the first to explore the impact of human capital expansion on the upgrading of Chinese processing trade at the micro level, which enriches the literature on the determinants of Chinese processing trade transformation and upgrading. Second, it uses the higher education reform implemented by the Chinese government in 1999 as a quasi-natural experiment and investigates the causal effects of human capital expansion on the upgrading of Chinese processing trade by adopting the difference-in-differences technique. Third, it constructs a comprehensive system for evaluating the upgrading of processing trade in the context of the open economy and global value chain. Last but not least, it explores the mechanisms through which human capital expansion affects the upgrading of processing trade and deepens our understanding of the internal relationship between the two. In addition, this paper examines the heterogeneous effects of human capital expansion on the upgrading of processing trade from multiple perspectives.
Since the reform and opening up, Chinese processing trade has developed rapidly. However, most of it remains in the stage of OEM production, lacking self-owned brands and core technologies, and its export expansion is mainly driven by a large number of low-value-added primary processed goods. Problems persist, such as an insufficient ability to conduct independent research and development and a low ability to acquire added value; hence, Chinese processing trade is located in the middle and low end of the global value chain. In the context of the new type of international division of labor, it is urgent for Chinese processing trade to transform and upgrade. This paper treats the sharp increase in human capital resulting from the higher education reform as a quasi-natural experiment and adopts a difference-in-differences method to empirically investigate the impact of human capital expansion on the upgrading of Chinese processing trade. Based on Chinese firm-level data from 2000 to 2013, the results show that human capital expansion significantly raises processing firms' export technological sophistication and thus promotes the upgrading of Chinese processing firms. The mechanism tests show that human capital expansion not only spurs processing firms to increase R&D and on-the-job training expenditures but also inspires processing firms to import and use more varieties and higher quality intermediate inputs. It also encourages processing firms to increase fixed investments. All of these factors jointly promote the upgrading of processing firms. Further heterogeneity analysis shows that the positive effect of human capital expansion is larger for processing firms with lower financing constraints, higher management efficiency, higher capital intensity, and foreign-owned processing firms. We also document heterogeneity in the impact of human capital expansion on the upgrading of processing firms across fields. Finally, this paper explores the relationship between human capital and the upgrading of processing firms from additional perspectives and finds that human capital expansion tends to promote the transformation of the organization mode from pure assembly processing trade to import-and-assembly processing trade, increase processing firms' domestic value added ratio, and increase processing firms' production efficiency and independent innovation ability. This paper has important policy implications. The government should continue to attach great importance to and actively promote the development of higher education and realize the transformation from "scale expansion" to "quality improvement",thereby continuously improving the quality of human capital in China. Processing trade firms should hire and absorb high quality human capital at all costs, increase funding for on-the-job training, and raise the human capital of current employees. This paper makes the following contributions. First, it is one of the first to explore the impact of human capital expansion on the upgrading of Chinese processing trade at the micro level, which enriches the literature on the determinants of Chinese processing trade transformation and upgrading. Second, it uses the higher education reform implemented by the Chinese government in 1999 as a quasi-natural experiment and investigates the causal effects of human capital expansion on the upgrading of Chinese processing trade by adopting the difference-in-differences technique. Third, it constructs a comprehensive system for evaluating the upgrading of processing trade in the context of the open economy and global value chain. Last but not least, it explores the mechanisms through which human capital expansion affects the upgrading of processing trade and deepens our understanding of the internal relationship between the two. In addition, this paper examines the heterogeneous effects of human capital expansion on the upgrading of processing trade from multiple perspectives.
引文
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李磊、冼国明、包群,2018:《“引进来”是否促进了“走出去”?——外商投资对中国企业对外直接投资的影响》,《经济研究》第3期。
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马述忠、张洪胜、王笑笑,2017:《融资约束与全球价值链地位提升——来自中国加工贸易企业的理论与证据》,《中国社会科学》第1期。
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曲建,2012:《我国加工贸易转型升级的战略思考》,《开放导报》第6期。
沈玉良、孙楚仁、徐美娜,2009:《贸易方式、生产控制与加工贸易企业转型升级》,《世界经济研究》第10期。
盛斌、毛其淋,2017:《进口贸易自由化是否影响了中国制造业出口技术复杂度》,《世界经济》第12期。
施炳展、曾祥菲,2015:《中国企业进口产品质量测算与事实》,《世界经济》第3期。
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孙浦阳、侯欣裕、盛斌,2018:《服务业开放、管理效率与企业出口》,《经济研究》第7期。
谭语嫣、谭之博、黄益平、胡永泰,2017:《僵尸企业的投资挤出效应:基于中国工业企业的证据》,《经济研究》第5期。
吴建新、刘德学,2010:《人力资本、国内研发、技术外溢与技术进步——基于中国省际面板数据和一阶差分广义矩方法的研究》,《世界经济文汇》第4期。
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许南、李建军,2010:《国际金融危机与中国加工贸易转型升级分析——基于全球生产网络视角》,《财贸经济》第4期。
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① 根据历年《中国统计年鉴》和《中国海关统计年鉴》计算得到。
(1)中国的大学本科教育通常为四年制,1999年“大学扩招”后大学毕业生大规模进入劳动力市场的首个年份是2003年。
(2)具体地,本文首先利用美国1980年数据测算ISIC3位码行业的人力资本强度指标,然后以HS6位码产品代码为“中介”将ISIC3位码行业对应到中国工业行业GB3位码上。
(3)由于鞋类制造业的人力资本强度在各行业中最低,与Che & Zhang(2017)类似,本文将该行业视为基准行业。
(4)由于中国工业企业数据库中企业研发投入指标在部分年份缺失,表3第(1)列回归所对应的样本期为2001—2003年、2005—2007年和2010年。
(5)另外,本文还采用研究开发费占企业销售收入的比重衡量研发创新,所得的结论一致。感谢审稿人的建议。
(6)其中,在职培训支出采用“1+培训支出”的自然对数值衡量。由于中国工业企业数据库中企业培训支出指标在部分年份缺失,表3第(2)列回归所对应的样本期为2001—2007年。
(7)本文还尝试进一步区分进口产品的不同贸易模式,即分别构造一般贸易模式下的进口种类与加工贸易模式下的进口种类指标进行估计,结果发现,人力资本扩张对企业进口种类的促进效应不受进口产品的贸易模式的影响。感谢审稿人的建议。
(8)考虑到在中国,与经济相对落后的中西部地区相比,大学毕业生可能更倾向于去经济较为发达的东部沿海地区就业,导致东部地区汇聚了大量的人力资本,该特征可能会对大学毕业生供给冲击的地区异质性影响产生干扰。受到数据可获得性的限制,目前尚不能对此进行分离,不过本文在回归中控制了“地区×年份”固定效应,这可以在一定程度上缓解上述问题导致的偏差。感谢审稿人指出这一问题。
(9)借鉴孙灵燕和李荣林(2011)的做法,采用利息支出占企业固定资产投资的比重来衡量企业融资约束,如果该比值越高,意味着企业面临的融资约束程度越小。
(10)具体而言,将企业期初的资本劳动比从低到高进行排序,据此将企业分为五组,相应的得到五个资本劳动比分组虚拟变量(Quantile1—Quantile5),其中Quantile1表示资本劳动比最低的企业虚拟变量,Quantile5表示资本劳动比最高的企业虚拟变量。在此基础上,将企业资本劳动比分组虚拟变量与Humcap×Post03形成三重交叉项,并将它们加入到基准倍差法模型进行估计。
(11)笔者也尝试在进行三重交叉项回归时加入变量之间的两两交叉项,发现本文的核心结论仍然成立。
(12)由于2007年及其之后年份的中国海关贸易数据库不再详细报告加工贸易的具体方式(来料加工与进料加工),故此处估计所用的样本期为2000—2006年。表5第(2)列与此相同。
(13)受数据可获得性的限制,本文测算了2000—2007年加工贸易企业出口DVAR指标,故表5第(3)列回归所对应的样本期为2000—2007年。
(14)这套数据库来自中国国家专利局,具体包括发明专利、实用新型专利和外观设计专利三种类型,本文使用了其中2000—2011年的样本。
(15)考虑到有些企业没有专利申请,因此,本文采用“1+企业专利申请数”的自然对数值来衡量lnPat_T。下同。
陈斌开、张川川,2016:《人力资本和中国城市住房价格》,《中国社会科学》第5期。
范子英、田彬彬,2014:《出口退税政策与中国加工贸易的发展》,《世界经济》第4期。
纪雯雯、赖德胜,2016:《人力资本结构与创新》,《北京师范大学学报(社科版)》第5期。
赖明勇、张新、彭水军、包群,2005:《经济增长的源泉:人力资本、研究开发与技术外溢》,《中国社会科学》第2期。
李兵、岳云嵩、陈婷,2016:《出口与企业自主技术创新:来自企业专利数据的经验研究》,《世界经济》第12期。
李磊、冼国明、包群,2018:《“引进来”是否促进了“走出去”?——外商投资对中国企业对外直接投资的影响》,《经济研究》第3期。
刘德学、李晓姗,2010:《加工贸易升级机制实证分析》,《国际经贸探索》第8期。
刘晴、徐蕾,2013:《对加工贸易福利效应和转型升级的反思——基于异质性企业贸易理论的视角》,《经济研究》第9期。
隆国强、张丽平,2012:《加工贸易转型升级的方向与政策》,《开放导报》第6期。
马述忠、张洪胜、王笑笑,2017:《融资约束与全球价值链地位提升——来自中国加工贸易企业的理论与证据》,《中国社会科学》第1期。
马双、张劼、朱喜,2012:《最低工资对中国就业和工资水平的影响》,《经济研究》第5期。
毛其淋、方森辉,2018:《创新驱动与中国制造业企业出口技术复杂度》,《世界经济与政治论坛》第2期。
曲建,2012:《我国加工贸易转型升级的战略思考》,《开放导报》第6期。
沈玉良、孙楚仁、徐美娜,2009:《贸易方式、生产控制与加工贸易企业转型升级》,《世界经济研究》第10期。
盛斌、毛其淋,2017:《进口贸易自由化是否影响了中国制造业出口技术复杂度》,《世界经济》第12期。
施炳展、曾祥菲,2015:《中国企业进口产品质量测算与事实》,《世界经济》第3期。
孙灵燕、李荣林,2011:《融资约束限制中国企业出口参与吗》,《经济学(季刊)》第4期。
孙浦阳、侯欣裕、盛斌,2018:《服务业开放、管理效率与企业出口》,《经济研究》第7期。
谭语嫣、谭之博、黄益平、胡永泰,2017:《僵尸企业的投资挤出效应:基于中国工业企业的证据》,《经济研究》第5期。
吴建新、刘德学,2010:《人力资本、国内研发、技术外溢与技术进步——基于中国省际面板数据和一阶差分广义矩方法的研究》,《世界经济文汇》第4期。
许和连、亓朋、祝树金,2006:《贸易开放度、人力资本与全要素生产率:基于中国省际面板数据的经验分析》,《世界经济》第12期。
许南、李建军,2010:《国际金融危机与中国加工贸易转型升级分析——基于全球生产网络视角》,《财贸经济》第4期。
杨建芳、龚六堂、张庆华,2006:《人力资本形成及其对经济增长的影响——一个包含教育和健康投入的内生增长模型及其检验》,《管理世界》第5期。
余淼杰、崔晓敏、袁东,2017:《最低工资和出口的国内附加值——来自中国企业层面证据》,北京大学中国经济研究中心讨论稿系列,No.C2017006.
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① 根据历年《中国统计年鉴》和《中国海关统计年鉴》计算得到。
(1)中国的大学本科教育通常为四年制,1999年“大学扩招”后大学毕业生大规模进入劳动力市场的首个年份是2003年。
(2)具体地,本文首先利用美国1980年数据测算ISIC3位码行业的人力资本强度指标,然后以HS6位码产品代码为“中介”将ISIC3位码行业对应到中国工业行业GB3位码上。
(3)由于鞋类制造业的人力资本强度在各行业中最低,与Che & Zhang(2017)类似,本文将该行业视为基准行业。
(4)由于中国工业企业数据库中企业研发投入指标在部分年份缺失,表3第(1)列回归所对应的样本期为2001—2003年、2005—2007年和2010年。
(5)另外,本文还采用研究开发费占企业销售收入的比重衡量研发创新,所得的结论一致。感谢审稿人的建议。
(6)其中,在职培训支出采用“1+培训支出”的自然对数值衡量。由于中国工业企业数据库中企业培训支出指标在部分年份缺失,表3第(2)列回归所对应的样本期为2001—2007年。
(7)本文还尝试进一步区分进口产品的不同贸易模式,即分别构造一般贸易模式下的进口种类与加工贸易模式下的进口种类指标进行估计,结果发现,人力资本扩张对企业进口种类的促进效应不受进口产品的贸易模式的影响。感谢审稿人的建议。
(8)考虑到在中国,与经济相对落后的中西部地区相比,大学毕业生可能更倾向于去经济较为发达的东部沿海地区就业,导致东部地区汇聚了大量的人力资本,该特征可能会对大学毕业生供给冲击的地区异质性影响产生干扰。受到数据可获得性的限制,目前尚不能对此进行分离,不过本文在回归中控制了“地区×年份”固定效应,这可以在一定程度上缓解上述问题导致的偏差。感谢审稿人指出这一问题。
(9)借鉴孙灵燕和李荣林(2011)的做法,采用利息支出占企业固定资产投资的比重来衡量企业融资约束,如果该比值越高,意味着企业面临的融资约束程度越小。
(10)具体而言,将企业期初的资本劳动比从低到高进行排序,据此将企业分为五组,相应的得到五个资本劳动比分组虚拟变量(Quantile1—Quantile5),其中Quantile1表示资本劳动比最低的企业虚拟变量,Quantile5表示资本劳动比最高的企业虚拟变量。在此基础上,将企业资本劳动比分组虚拟变量与Humcap×Post03形成三重交叉项,并将它们加入到基准倍差法模型进行估计。
(11)笔者也尝试在进行三重交叉项回归时加入变量之间的两两交叉项,发现本文的核心结论仍然成立。
(12)由于2007年及其之后年份的中国海关贸易数据库不再详细报告加工贸易的具体方式(来料加工与进料加工),故此处估计所用的样本期为2000—2006年。表5第(2)列与此相同。
(13)受数据可获得性的限制,本文测算了2000—2007年加工贸易企业出口DVAR指标,故表5第(3)列回归所对应的样本期为2000—2007年。
(14)这套数据库来自中国国家专利局,具体包括发明专利、实用新型专利和外观设计专利三种类型,本文使用了其中2000—2011年的样本。
(15)考虑到有些企业没有专利申请,因此,本文采用“1+企业专利申请数”的自然对数值来衡量lnPat_T。下同。