THE FUTURE OF EMPLOYMENT

>  Carl Benedikt Frey and Michael A. Osborne

> September 17, 2013

## Abstract

我们研究了容易被计算机化的敏感工作，为了对此进行评估，我们首先使用高斯过程分类器实现了一个新的方法去评估702种详细工作被计算机化的概率。基于这些估计，我们研究了未来电脑化对美国劳动力市场结果的预期影响，主要目的是分析面临风险的工作岗位数量以及职业电脑化概率、工资和教育程度之间的关系。根据我们的估计，全美国有百分之四十七的的职业暴露在风险之中。我们进一步提供的证据表明，工资和教育程度与职业的计算机化概率呈强烈的负相关。

We examine how susceptible jobs are to computerisation. To assess this, we begin by implementing a novel methodology to estimate the probability of computerisation for 702 detailed occupations, using a Gaussian process classifier. Based on these estimates, we examine expected impacts of future computerisation on US labour market outcomes, with the primary objective of analysing the number of jobs at risk and the relationship between an occupation’s probability of computerisation, wages and educational attainment. According to our estimates, about 47 percent of total US employment is at risk. We further provide evidence that wages and educational attainment exhibit a strong negative relationship with an occupation' s probability of computerisation.

## I. Introduction

在这篇论文中，我们要解决的问题是：工作对计算机化的影响有多大？在现有文献的基础上我们有两种方式。第一种是使用机器学习和移动机器人。我们开发了一种新的方法依据各个职业对计算机化的敏感性去对职业进行分类。其次，我们采用这种方法来估计702个详细职业的计算机化概率，并研究未来计算机化对美国劳动力市场结果的预期影响。

In this paper, we address the question: how susceptible are jobs to computerisation? Doing so, we build on the existing literature in two ways. First, drawing upon recent advances in Machine Learning (ML) and Mobile Robotics (MR), we develop a novel methodology to categorise occupations according to their susceptibility to computerisation.1 Second, we implement this methodology to estimate the probability of computerisation for 702 detailed occupations, and examine expected impacts of future computerisation on US labour market outcomes.

我们的论文的动机是约翰·梅纳德·凯恩斯（John Maynard Keynes）经常被引用的关于普遍技术失业的预测，“因为我们发现了节约劳动力使用的方法，超过了我们发现劳动力新用途的速度”（Keynes，1933，第3页）。事实上，在过去的几十年里，计算机已经取代了许多工作，包括记帐员、收银员和电话接线员的职能（Bresnahan，1999；MGI，2013）。最近，发达经济体劳动力市场的糟糕表现加剧了经济学家之间关于技术失业的争论。尽管人们对持续高失业率背后的驱动力仍存在分歧，但许多学者指出，计算机控制的设备可能是最近失业率增长的一种解释（例如，见 Brynjolfsson 和McAfee，2011）。

Our paper is motivated by John Maynard Keynes’s frequently cited prediction of widespread technological unemployment “due to our discovery of means of economising the use of labour outrunning the pace at which we can find new uses for labour” (Keynes, 1933, p. 3). Indeed, over the past decades, computers have substituted for a number of jobs, including the functions of bookkeepers, cashiers and telephone operators (Bresnahan, 1999;MGI, 2013). More recently, the poor performance of labour markets across advanced economies has intensified the debate about technological unemployment among economists. While there is ongoing disagreement about the driving forces behind the persistently high unemployment rates, a number of scholars have pointed at computer-controlled equipment as a possible explanation for recent jobless growth (see, for example, Brynjolfsson and McAfee, 2011).

计算机化对劳动力市场结果的影响在文献中得到了证实，记录了常规密集型职业的就业率下降，即主要由遵循明确程序的任务组成的职业，这些程序可以通过复杂的算法轻松执行。例如，Charles等人（2013）以及Jaimovich和Siu（2012）的研究强调，制造业就业的持续下降和其他常规工作的消失导致了目前的低就业率。

The impact of computerisation on labourmarket outcomes is well-established in the literature, documenting the decline of employment in routine intensive occupations – i.e. occupationsmainly consisting of tasks followingwell-defined procedures that can easily be performed by sophisticated algorithms. For example, studies by Charles, et al. (2013) and Jaimovich and Siu (2012) emphasise that the ongoing decline in manufacturing employment and the disappearance of other routine jobs is causing the current low rates of employment.

除了常规制造任务的计算机化外，Autor和Dorn（2013）还记录了劳动力市场的结构性转变，工人将劳动力供应从中等收入制造业重新分配到低收入服务业。可以说，这是因为服务职业的手工任务不太容易被计算机化，因为它们需要更高程度的灵活性和身体适应性（Autor等人，2003；Goos 和Manning，2007年；Autor和Dorn，2013年）。

In addition to the computerisation of routine manufacturing tasks, Autor and Dorn(2013) document a structural shift in the labour market, with workers reallocating their labour supply from middle-income manufacturing to low-income service occupations. Arguably, this is because the manual tasks of service occupations are less susceptible to computerisation, as they require a higher degree of flexibility and physical adaptability (Autor, et al., 2003; Goos and Manning, 2007; Autor and Dorn, 2013).

与此同时，随着计算机价格的下跌，解决问题的技能变得相对高效，这解释了在涉及认知任务的职业中，熟练劳动力具有相对优势，就业人数大幅增长，以及教育回报率持续增加（Katz和Murphy，1992；Acemoglu，2002年；Autor和Dorn，2013年）。Goos和Manning（2007）最近的一篇文章的标题“糟糕而可爱的工作”抓住了当前劳动力市场两极分化趋势的本质，高收入认知工作和低收入体力工作的就业人数不断增加，同时中等收入日常工作也被掏空。

At the same time, with falling prices of computing, problem-solving skills are becoming relatively productive, explaining the substantial employment growth in occupations involving cognitive tasks where skilled labour has a comparative advantage, as well as the persistent increase in returns to education (Katz and Murphy, 1992; Acemoglu, 2002; Autor and Dorn, 2013). The title “Lousy and Lovely Jobs”, of recent work by Goos and Manning (2007), thus captures the essence of the current trend towards labour market polarization, with growing employment in high-income cognitive jobs and low-income manual occupations, accompanied by a hollowing-out of middle-income routine jobs.

Brynjolfsson 和 McAfee（2011）认为，技术创新的步伐仍在加快，更复杂的软件技术通过裁员扰乱了劳动力市场。他们书中的例子引人注目的是，计算机化不再局限于日常制造任务。谷歌开发的自动驾驶无人驾驶汽车提供了一个例子，说明运输和物流中的手动任务可能很快就会实现自动化。在“一个领域接一个领域，计算机领先”一节中，他们强调了这些发展的速度有多快。不到十年前，Levy和Murnane（2004）在“为什么人仍然重要”一章中指出了复制人类感知的困难，断言在车流中驾驶不受自动化影响：“但在迎面而来的车流中执行左转涉及到如此多的因素，很难想象会发现一套可以复制驾驶员行为的规则[…]”。六年后的2010年10月，谷歌宣布已将几辆丰田普锐斯改装为全自动驾驶（Brynjolfsson和McAfee，2011）。

According to Brynjolfsson and McAfee (2011), the pace of technological innovation is still increasing, with more sophisticated software technologies disrupting labour markets by making workers redundant. What is striking about the examples in their book is that computerisation is no longer confined to routine manufacturing tasks. The autonomous driverless cars, developed by Google, provide one example of how manual tasks in transport and logistics may soon be automated. In the section “In Domain After Domain, Computers Race Ahead”, they emphasise how fast moving these developments have been. Less than ten years ago, in the chapter “Why People Still Matter”, Levy and Murnane (2004) pointed at the difficulties of replicating human perception, asserting that driving in traffic is insusceptible to automation: “But executing a left turn against oncoming traffic involves so many factors that it is hard to imagine discovering the set of rules that can replicate a driver’s behaviour [. . . ]”. Six years later, in October 2010, Google announced that it had modified several Toyota Priuses to be fully autonomous (Brynjolfsson and McAfee, 2011).

据我们所知，尚未有研究量化近期技术进步对未来就业可能意味着什么。 本研究旨在弥补文献中的这一空白。 尽管确实存在有用的框架来检查计算机对职业就业构成的影响，但它们似乎不足以解释超出日常任务计算机化范围的技术趋势的影响。 Autor 等人的开创性工作（2003）。 例如，一方面区分了认知任务和体力任务，另一方面区分了常规任务和非常规任务。 虽然计算机对认知和手动例行任务的替代是显而易见的，但非常规任务涉及从法律写作、卡车驾驶和医疗诊断到说服和销售的一切。 

在目前的研究中，我们将认为法律写作和卡车驾驶很快就会自动化，而例如说服这种技能则不会。根据工程科学的最新发展，特别是ML领域的进展，包括数据挖掘、机器视觉、计算统计学和人工智能的其他子领域，以及MR，我们得出了理解工作对计算机化的易感性所需的额外维度。

不用说，许多因素正在推动决策自动化，而我们无法全面了解这些因素。相反，从技术能力的角度来看，我们的目标是确定工程师需要解决哪些问题才能实现特定职业的自动化。通过强调这些问题、它们的困难以及它们所涉及的职业，我们根据它们对计算机化的易感性对工作进行了分类。利用O*NET数据，这些问题的特征与不同的职业特征相匹配，使我们能够从技术变革对劳动力市场职业构成的影响以及这些技术实现后面临风险的工作岗位数量的角度来研究技术变革的未来方向。

To our knowledge, no study has yet quantified what recent technological progress is likely to mean for the future of employment. The present study intends to bridge this gap in the literature. Although there are indeed existing useful frameworks for examining the impact of computers on the occupational employment composition, they seem inadequate in explaining the impact of technological trends going beyond the computerisation of routine tasks. Seminal work by Autor, et al. (2003), for example, distinguishes between cognitive and manual tasks on the one hand, and routine and non-routine tasks on the other. While the computer substitution for both cognitive and manual routine tasks is evident, non-routine tasks involve everything from legal writing, truck driving and medical diagnoses, to persuading and selling. 

In the present study, we will argue that legal writing and truck driving will soon be automated, while persuading, for instance, will not. Drawing upon recent developments in Engineering Sciences, and in particular advances in the fields of ML, including Data Mining, Machine Vision, Computational Statistics and other sub-fields of Artificial Intelligence, as well as MR, we derive additional dimensions required to understand the susceptibility of jobs to computerisation.

Needless to say, a number of factors are driving decisions to automate and we cannot capture these in full. Rather we aim, from a technological capabilities point of view, to determine which problems engineers need to solve for specific occupations to be automated. By highlighting these problems, their difficulty and to which occupations they relate, we categorise jobs according to their susceptibility to computerisation. The characteristics of these problems were matched to different occupational characteristics, using O∗NET data, allowing us to examine the future direction of technological change in terms of its impact on the occupational composition of the labour market, but also the number of jobs at risk should these technologies materialise.

本研究涉及两篇文献。首先，我们的分析建立在关于就业任务内容的劳动经济学文献的基础上（Autor，et al.，2003；Goos和Manning，2007；Autor和Dorn，2013）。基于计算机工作的定义前提，本文献考察了计算机化对劳动力市场职业构成的历史影响。然而，计算机的作用范围最近有所扩大，并将不可避免地继续扩大（Brynjolfsson和McAfee，2011；MGI，2013）。根据ML的最新进展，我们扩展了计算机现在和将来适合完成的任务的前提。这样，我们就以前瞻性的方式建立在任务内容文献的基础上。此外，尽管这些文献主要集中在1991年修订的《职业头衔词典》（DOT）中的任务衡量标准上，但我们依赖于2010年版的DOT继任者O\*NET——一项为美国劳工部开发的在线服务。因此，O\*NET的优势在于提供有关职业工作活动的最新信息。

The present study relates to two literatures. First, our analysis builds on the labour economics literature on the task content of employment (Autor, et al., 2003; Goos and Manning, 2007; Autor and Dorn, 2013). Based on defined premises about what computers do, this literature examines the historical impact of computerisation on the occupational composition of the labour market. However, the scope of what computers do has recently expanded, and will inevitably continue to do so (Brynjolfsson and McAfee, 2011; MGI, 2013). Drawing upon recent progress in ML, we expand the premises about the tasks computers are and will be suited to accomplish. Doing so, we build on the task content literature in a forward-looking manner. Furthermore, whereas this literature has largely focused on task measures from the Dictionary of Occupational Titles (DOT), last revised in 1991, we rely on the 2010 version of the DOT successor O∗NET – an online service developed for the US Department of Labor. Accordingly, O∗NET has the advantage of providing more recent information on occupational work activities.

其次，我们的研究涉及研究基于信息的任务向外国工作场所转移的文献（Jensen和Kletzer，2005；Blinder，2009年；Jensen和Kletzer，2010年；奥尔登斯基，2012年；Blinder和Krueger，2013）。这些文献包括不同的方法，根据职业对离岸外包的易感性对其进行排名和分类。例如，Blinder（2009）利用关于不同职业工作性质的O*NET数据估计，在未来一二十年内，美国22%至29%的工作可以或将可以离岸外包。这些估计是基于不能外包的工作的两个明确特征：（a）工作必须在特定的工作地点进行；以及（b）该工作需要面对面的个人交流。自然，可以离岸的职业的特征与可以自动化的职业的特点不同。例如，收银员的工作在很大程度上被自助服务技术所取代，必须在特定的工作地点进行，并且需要面对面的接触。因此，计算机化的程度很可能超出离岸外包的范围。因此，尽管我们的方法实施与Blinder（2009）的方法类似，但我们依赖于不同的职业特征。

Second, our study relates to the literature examining the offshoring of information-based tasks to foreign worksites (Jensen and Kletzer, 2005; Blinder, 2009; Jensen and Kletzer, 2010; Oldenski, 2012; Blinder and Krueger, 2013). This literature consists of different methodologies to rank and categorise occupations according to their susceptibility to offshoring. For example, using O∗NET data on the nature of work done in different occupations, Blinder (2009) estimates that 22 to 29 percent of US jobs are or will be offshorable in the next decade or two. These estimates are based on two defining characteristics of jobs that cannot be offshored: (a) the job must be performed at a specific work location; and (b) the job requires face-to-face personal communication. Naturally, the characteristics of occupations that can be offshored are different from the characteristics of occupations that can be automated. For example, the work of cashiers, which has largely been substituted by self- service technology, must be performed at specific work location and requires face-to-face contact. The extent of computerisation is therefore likely to go beyond that of offshoring. Hence, while the implementation of our methodology is similar to that of Blinder (2009), we rely on different occupational characteristics.

本文的其余部分结构如下。在第二节中，我们回顾了有关技术进步与就业之间历史关系的文献。第三节介绍了最近和预期的未来技术发展。在第四节，我们描述了我们的方法，在第五节，我们研究了这些技术发展对劳动力市场结果的预期影响。最后，在第六节中，我们得出了一些结论。

The remainder of this paper is structured as follows. In Section II, we review the literature on the historical relationship between technological progress and employment. Section III describes recent and expected future technological developments. In Section IV, we describe our methodology, and in Section V, we examine the expected impact of these technological developments on labour market outcomes. Finally, in Section VI, we derive some conclusions.

## II. A HISTORY OF TECHNOLOGICAL REVOLUTIONS AND EMPLOYMENT

对技术失业的担忧并不是最近才出现的现象。纵观历史，技术发明之后的创造性破坏过程创造了巨大的财富，但也造成了不希望的破坏。正如熊彼特（1962）所强调的那样，并不是缺乏创造性的想法为经济发展设定了界限，而是强大的社会和经济利益推动了技术现状。威廉·李（William Lee）的例子很好地说明了这一点，他在1589年发明了袜架针织机，希望它能减轻工人手工编织的负担。为了寻求他的发明的专利保护，他前往伦敦，在那里他租了一栋大楼让伊丽莎白女王一世观看他的机器。令他失望的是，女王更关心他的发明对就业的影响，拒绝授予他专利，声称：“李大师，你的目标很高。想想这项发明能给我可怜的臣民带来什么。它肯定会剥夺他们的就业机会，从而使他们成为乞丐，从而给他们带来毁灭”（引用于Acemoglu和Robinson，2012年，第182f页）。女王的担忧很可能是因为骑士团担心这项发明会使其工匠成员的技能过时。5骑士团的反对确实如此强烈，以至于威廉·李不得不离开英国。

The concern over technological unemployment is hardly a recent phenomenon. Throughout history, the process of creative destruction, following technological inventions, has created enormous wealth, but also undesired disruptions. As stressed by Schumpeter (1962), it was not the lack of inventive ideas thatset the boundaries for economic development, but rather powerful social and economic interests promoting the technological status quo. This is nicely illustrated by the example of William Lee, inventing the stocking frame knitting machine in 1589, hoping that it would relieve workers of hand-knitting. Seeking patent protection for his invention, he travelled to London where he had rented a building for his machine to be viewed by Queen Elizabeth I. To his disappointment, the Queen was more concerned with the employment impact of his invention and refused to grant him a patent, claiming that: “Thou aimest high, Master Lee. Consider thou what the invention could do to my poor subjects. It would assuredly bring to them ruin by depriving them of employment, thus making them beggars” (cited in Acemoglu and Robinson, 2012, p. 182f). Most likely the Queen’s concern was a manifestation of the hosiers’ guilds fear that the invention would make the skills of its artisan members obsolete.5 The guilds’ opposition was indeed so intense that William Lee had to leave Britain.

Kellenbenz（1974年，第243页）有说服力地认为，行会系统地试图削弱作为聚合者的市场力量，以维持技术现状，并指出“行会保护其成员的利益不受外来者的影响，其中包括发明者，他们用新的设备和技术威胁要扰乱其成员的经济地位。正如Mokyr（1998年，第11页）所指出的：“除非所有人都接受市场结果的“判决”，否则是否采用创新的决定很可能会受到失败者通过非市场机制和政治激进主义的抵制。”因此，工人可能会抵制新技术，因为它们会使他们的技能过时，并不可逆转地减少他们的预期收入。因此，就业保护和技术进步之间的平衡在很大程度上反映了社会权力的平衡，以及技术进步的收益是如何分配的。

That guilds systematically tried to weaken market forces as aggregators to maintain the technological status quo is persuasively argued by Kellenbenz (1974, p. 243), stating that “guilds defended the interests of their members against outsiders, and these included the inventors who, with their new equipment and techniques, threatened to disturb their members’ economic status.”As pointed out by Mokyr (1998, p. 11): “Unless all individuals accept the“verdict” of the market outcome, the decision whether to adopt an innovation is likely to be resisted by losers through non-market mechanism and political activism.” Workers can thus be expected to resist new technologies, insofar that they make their skills obsolete and irreversibly reduce their expected earnings. The balance between job conservation and technological progress therefore, to a large extent, reflects the balance of power in society, and how gains from technological progress are being distributed.

英国工业革命生动地说明了这一点。尽管英国的工艺协会仍然广泛存在于欧洲大陆，但到1688年光荣革命时，它已经衰落并失去了大部分政治影响力（Nef，1957，第26和32页）。随着议会凌驾于王室之上，1769年通过了一项立法，规定破坏机械可判处死刑（Mokyr，1990，第257页）。可以肯定的是，机械化仍然存在阻力。1811年至1816年间的“卢德派”骚乱在一定程度上反映了工人对技术变革的恐惧，因为议会撤销了1551年禁止在羊毛加工行业使用零工厂的法律。然而，英国政府对试图阻止技术进步的团体采取了越来越严厉的态度，并部署了12000人对抗暴徒（Mantoux，2006，第403-8页）。1779年兰开夏郡骚乱后通过的一项决议解释了政府对破坏机械的情绪，指出：“大骚乱的唯一原因是棉花生产中使用的新机器；尽管如此，该国从这些机器的安装中受益匪浅，在这个国家摧毁这些机器只会成为将它们转移到另一个国家的手段，损害英国的贸易”（引用于Mantoux，2006年，第403页）。

The British Industrial Revolution illustrates this point vividly. While still widely present on the Continent, the craft guild in Britain had, by the time of the Glorious Revolution of 1688, declined and lost most of its political clout (Nef, 1957, pp. 26 and 32). With Parliamentary supremacy established over the Crown, legislation was passed in 1769 making the destruction of machinery punishable by death (Mokyr, 1990, p. 257). To be sure, there was still resistance to mechanisation. The “Luddite” riots between 1811 and 1816 were partly a manifestation of the fear of technological change among workers as Parliament revoked a 1551 law prohibiting the use of gig mills in the wool-finishing trade. The British government however took an increasingly stern view on groups attempting to halt technological progress and deployed 12,000 men against the rioters (Mantoux, 2006, p. 403-8). The sentiment of the government towards the destruction of machinery was explained by a resolution passed after the Lancashire riots of 1779, stating that: “The sole cause of great riots was the new machines employed in cotton manufacture; the country notwithstanding has greatly benefited from their erection [and] destroying them in this country would only be the means of transferring them to another [. . . ] to the detriment of the trade of Britain” (cited in Mantoux, 2006, p. 403).

对于人们对技术进步态度的转变，至少有两种可能的解释。首先，在议会凌驾于王室之上之后，拥有财产的阶层在英国政治上占据主导地位（North and Weingast，1989）。由于各种制造技术的扩散并没有对其资产的价值造成风险，而且一些财产所有者将从制成品的出口中受益，工匠们根本没有压制他们的政治权力。其次，发明者、消费者和非熟练工厂工人在很大程度上受益于机械化（Mokyr，1990，第256和258页）。甚至有人认为，尽管对机械化的就业问题感到担忧，但非熟练工人一直是工业革命的最大受益者（Clark，2008）。7尽管有相互矛盾的证据表明，资本所有者最初积累的国民收入份额越来越大（Allen，2009a），同样有证据表明实际工资在增长（Lindert和Williamson，1983；Feinstein，1998年）。这意味着，尽管制造技术使工匠的技能过时，但技术进步带来的收益的分配方式逐渐使越来越多的劳动力受益。

There are at least two possible explanations for the shift in attitudes towards technological progress. First, after Parliamentary supremacy was established over the Crown, the property owning classes became politically dominant in Britain (North and Weingast, 1989). Because the diffusion of various manufacturing technologies did not impose a risk to the value of their assets, and some property owners stood to benefit from the export of manufactured goods, the artisans simply did not have the political power to repress them. Second, inventors, consumers and unskilled factory workers largely benefited from mechanisation (Mokyr, 1990, p. 256 and 258). It has even been argued that, despite the employment concerns over mechanisation, unskilled workers have been the greatest beneficiaries of the Industrial Revolution (Clark, 2008).7 While there is contradictory evidence suggesting that capital owners initially accumulated a growing share of national income (Allen, 2009a), there is equally evidence of growing real wages (Lindert and Williamson, 1983; Feinstein, 1998). This implies that although manufacturing technologies made the skills of artisans obsolete, gains from technological progress were distributed in a manner that gradually benefited a growing share of the labour force.

十九世纪制造技术的一个重要特征是，它们在很大程度上是“去中心化”的，即通过简化任务来取代技能（Braverman，1974；Hounshell，1985；James和Skinner，1985；Goldin和Katz，1998）。随着工厂系统开始取代手工作坊，去填充过程也随之发生，随着蒸汽动力的采用，生产越来越机械化，这一过程加快了步伐（Goldin和Sokoloff，1982；阿塔克等人，2008a）。以前由工匠完成的工作现在被分解成更小的、高度专业化的序列，需要更少的技能，但需要更多的工人来完成。9一些创新甚至被设计为去毛刺。例如，可互换零件的先驱伊莱·惠特尼（Eli Whitney）将这项技术的目标描述为“用正确有效的机械操作来代替艺术家只有通过长期实践和经验才能获得的技能；这种技能在这个国家在很大程度上是不具备的”（Habakkuk，1962，第22页）。

An important feature of nineteenth century manufacturing technologies is that they were largely “deskilling” – i.e. they substituted for skills through the simplification of tasks (Braverman, 1974; Hounshell, 1985; James and Skinner, 1985; Goldin and Katz, 1998). The deskilling process occurred as the factory system began to displace the artisan shop, and it picked up pace as production increasingly mechanized with the adoption of steam power (Goldin and Sokoloff, 1982; Atack, et al., 2008a). Work that had previously been performed by artisans was now decomposed into smaller, highly specialised, sequences, requiring less skill, but more workers, to perform.9 Some innovations were even designed to be deskilling. For example, Eli Whitney, a pioneer of interchangeable parts, described the objective of this technology as “to substitute correct and effective operations of machinery for the skill of the artist which is acquired only by long practice and experience; a species of skill which is not possessed in this country to any considerable extent” (Habakkuk, 1962, p. 22).

再加上连续流生产的发展，使工人能够在不同的任务转移到他们身上时保持静止，正是相同的可互换零件使复杂的产品能够通过使用高度专业化的机床按照一系列操作从大规模生产的单个部件组装而成。然而，尽管第一条装配线记录于1804年，但直到19世纪末，连续流工艺才开始被更大规模地采用，这使得福特汽车公司等公司能够以足够低的价格生产T-Ford，使其成为人们的汽车（Mokyr，1990，第137页）。至关重要的是，福特于1913年推出的新装配线是专门为非熟练工人操作的机械而设计的（Hounshell，1985，第239页）。此外，以前的一人工作变成了29人的工作，使总工作时间减少了34%（Bright，1958）。因此，福特汽车公司的例子突出了19世纪观察到的一般模式，实物资本为非熟练劳动力提供了相对的补充，同时取代了相对熟练的工匠（James和Skinner，1985；Louis和Paterson，1986；Brown和Philips，1986；Atack等人，2004年）。因此，正如Acemoglu（2002年，第7页）所指出的：“技术进步有利于更多技术工人的想法是20世纪的现象。”换言之，经济历史学家的传统观点表明，资本深化对技术劳动力相对需求的影响在19世纪和20世纪之间是不连续的。

Together with developments in continuous-flow production, enabling workers to be stationary while different tasks were moved to them, it was identical interchangeable parts that allowed complex products to be assembled from mass produced individual components by using highly specialised machine tools to a sequence of operations. Yet while the first assembly-line was documented in 1804, it was not until the late nineteenth century that continuous-flow processes started to be adopted on a larger scale, which enabled corporations such as the Ford Motor Company to manufacture the T-Ford at a sufficiently low price for it to become the people’s vehicle (Mokyr, 1990, p. 137). Crucially, the new assembly line introduced by Ford in 1913 was specifically designed for machinery to be operated by unskilled workers (Hounshell, 1985, p. 239). Furthermore, what had previously been a one-man job was turned into a 29-man worker operation, reducing the overall work time by 34 percent (Bright, 1958). The example of the Ford Motor Company thus underlines the general pattern observed in the nineteenth century, with physical capital providing a relative complement to unskilled labour, while substituting for relatively skilled artisans (James and Skinner, 1985; Louis and Paterson, 1986; Brown and Philips, 1986; Atack, et al., 2004). Hence, as pointed out by Acemoglu (2002, p. 7):“the idea that technological advances favor more skilled workers is a twentieth century phenomenon.” The conventional wisdom among economic historians, in other words, suggests a discontinuity between the nineteenth and twentieth century in the impact of capital deepening on the relative demand for skilled labour.

资本-技能互补的现代模式在19世纪末逐渐出现，因为制造业生产转向了日益机械化的装配线。这种转变可以追溯到从蒸汽和水力转向电力，再加上连续工艺和批量生产方法，减少了对许多搬运、运输和组装任务中非熟练体力工人的需求，但增加了对技能的需求（Goldin和Katz，1998）。简言之，尽管工厂装配线分工极端，需要大量的人工操作，但电气化使生产过程的许多阶段实现了自动化，这反过来又增加了对相对熟练的蓝领生产工人操作机器的需求。此外，电气化使白领非生产工人的比例不断增加（Goldin和Katz，1998）。在19世纪，随着蒸汽和水力技术的改进，企业规模越来越大，使它们能够采用动力机械，通过加强劳动分工和提高资本密集度来实现生产力增长（Atack等人，2008a）。此外，随着基础设施的普及和改善，运输革命降低了国内外货物运输成本（Atack等人，2008b）。早期的手工艺品市场主要局限于周边地区，因为运输成本相对于生产的商品价值来说很高。然而，随着运输革命，市场规模扩大，从而侵蚀了当地的垄断力量，这反过来又增加了竞争，迫使企业通过机械化提高生产力。随着企业规模的扩大和服务于地理位置扩展的市场，管理任务的数量和复杂性都在增加，需要更多的管理和职员（Chandler，1977）。到20世纪之交，电气化强化了这种模式，电气化不仅增加了相对熟练的蓝领劳动力的比例，还增加了对白领工人的需求（Goldin和Katz，1998），他们往往具有更高的教育程度（Allen，2001）。

The modern pattern of capital-skill complementarity gradually emerged in the late nineteenth century, as manufacturing production shifted to increasingly mechanised assembly lines. This shift can be traced to the switch to electricity from steam and water-power which, in combination with continuous-process and batch production methods, reduced the demand for unskilled manual workers in many hauling, conveying, and assembly tasks, but increased the demand for skills (Goldin and Katz, 1998). In short, while factory assembly lines, with their extreme division of labour, had required vast quantities of human operatives, electrification allowed many stages of the production process to be automated, which in turn increased the demand for relatively skilled blue-collar production workers to operate the machinery. In addition, electrification contributed to a growing share of white-collar nonproduction workers (Goldin and Katz, 1998). Over the course of the nineteenth century, establishments became larger in size as steam and water power technologies improved, allowing them to adopt powered machinery to realize productivity gains through the combination of enhanced division of labour and higher capital intensity (Atack, et al., 2008a). Furthermore, the transport revolution lowered costs of shipping goods domestically and internationally as infrastructure spread and improved (Atack, et al., 2008b). The market for artisan goods early on had largely been confined to the immediate surrounding area because transport costs were high relative to the value of the goods produced. With the transport revolution, however,market size expanded, thereby eroding local monopoly power, which in turn increased competition and compelled firms to raise productivity through mechanisation. As establishments became larger and served geographically expended markets, managerial tasks increased in number and complexity, requiring more managerial and clerking employees (Chandler, 1977). This pattern was, by the turn of the twentieth century, reinforced by electrification, which not only contributed to a growing share of relatively skilled blue-collar labour, but also increased the demand for white-collar workers (Goldin and Katz, 1998), who tended to have higher educational attainment (Allen, 2001).

自电气化以来，二十世纪的故事一直是教育和技术之间的竞赛（Goldin和Katz，2009）。美国高中运动恰逢办公室的第一次工业革命（Goldin和Katz，1995）。虽然打字机是在19世纪60年代发明的，但直到20世纪初，它才被引入办公室，当时它进入了一个机械化的浪潮，出现了口述录音机、计算器、模拟机、地址机和计算机的前身——按键机（Beniger，1986；Cortada，2000）。重要的是，这些办公机器降低了信息处理任务的成本，并增加了对补充因素的需求，即受过教育的上班族。然而，在高中运动之后，受过教育的上班族的供应增加，与书记员职业相对于生产工人的工资溢价大幅下降有关（Goldin和Katz，1995）。然而，这并不是取消计费技术变革的结果。文书工作人员确实受过相对的教育。相反，这是受过教育的工人的供应超过了对其技能的需求，导致教育工资差距缩小的结果。

Since electrification, the story of the twentieth century has been the race between education and technology (Goldin and Katz, 2009). The US high school movement coincided with the first industrial revolution of the office (Goldin and Katz, 1995). While the typewriter was invented in the 1860s, it was not introduced in the office until the early twentieth century, when it entered a wave of mechanisation, with dictaphones, calculators, mimeo machines, address machines, and the predecessor of the computer – the keypunch (Beniger, 1986; Cortada, 2000). Importantly, these office machines reduced the cost of information processing tasks and increased the demand for the complementary factor – i.e. educated office workers. Yet the increased supply of educated office workers, following the high school movement, was associated with a sharp decline in the wage premium of clerking occupations relative to production workers (Goldin and Katz, 1995). This was, however, not the result of deskilling technological change. Clerking workers were indeed relatively educated. Rather, it was the result of the supply of educated workers outpacing the demand for their skills, leading educational wage differentials to compress.

虽然美国的教育工资差距从1915年到1980年有所缩小（Goldin和Katz，2009），但自20世纪80年代以来，许多国家的教育工资差异和总体工资不平等都急剧增加（Krueger，1993；Murphy等人，1998年；阿特金森，2008年；Goldin和Katz，2009年）。尽管显然有几个变量在起作用，但人们普遍认为，这可以归因于计算机和信息技术的采用推动了资本-技能互补性的加速（Krueger，1993；Autor等人，1998年；Bresnahan等人，2002年）。通常所说的计算机革命始于1960年左右计算机的首次商业使用，并在20世纪90年代通过互联网和电子商务的发展而持续。1945年至1980年间，由于每次计算的成本以年均37%的速度下降（Nordhaus，2007），电话运营商被裁掉，通用汽车公司在20世纪60年代推出了第一个工业机器人，20世纪70年代，航空公司预订系统在自助服务技术方面处于领先地位（Gordon，2012）。在20世纪80年代和90年代，随着计算能力的激增，计算成本下降得更快，平均每年下降64%（Nordhaus，2007）。13与此同时，条形码扫描仪和提款机正在零售和金融行业普及，第一台个人电脑于20世纪80初推出，其文字处理和电子表格功能消除了复印打字员的职业，并允许重复计算实现自动化（Gordon，2012）。这种对劳动力的替代标志着另一个重要的逆转。20世纪初的办公机器增加了对职员的需求（Chandler，1977；Goldin和Katz，1995年）。以类似的方式，计算机化增加了对此类任务的需求，但也允许它们实现自动化（Autor等人，2003）。

While educational wage differentials in the US narrowed from 1915 to 1980 (Goldin and Katz, 2009), both educational wage differentials and overall wage inequality have increased sharply since the 1980s in a number of countries (Krueger, 1993; Murphy, et al., 1998; Atkinson, 2008; Goldin and Katz, 2009). Although there are clearly several variables at work, consensus is broad that this can be ascribed to an acceleration in capital-skill complementarity, driven by the adoption of computers and information technology (Krueger, 1993; Autor, et al., 1998; Bresnahan, et al., 2002). What is commonly referred to as the Computer Revolution began with the first commercial uses of computers around 1960 and continued through the development of the Internet and e-commerce in the 1990s. As the cost per computation declined at an annual average of 37 percent between 1945 and 1980 (Nordhaus, 2007), telephone operators were made redundant, the first industrial robot was introduced by General Motors in the 1960s, and in the 1970s airline reservations systems led the way in selfservice technology (Gordon, 2012). During the 1980s and 1990s, computing costs declined even more rapidly, on average by 64 percent per year, accompanied by a surge in computational power (Nordhaus, 2007).13 At the same time, bar-code scanners and cash machines were spreading across the retail and financial industries, and the first personal computers were introduced in the early 1980s, with their word processing and spreadsheet functions eliminating copy typist occupations and allowing repetitive calculations to be automated (Gordon, 2012). This substitution for labour marks a further important reversal.The early twentieth century office machines increased the demand for clerking workers (Chandler, 1977; Goldin and Katz, 1995). In a similar manner, computerisation augments demand for such tasks, but it also permits them to be automated (Autor, et al., 2003).

计算机革命可以在一定程度上解释过去几十年中日益严重的工资不平等。例如，Krueger（1993）发现，使用计算机的工人的收入比其他人高出约10%至15%，但计算机的使用在教育回报率的增长中占了很大一部分。此外，最近的研究发现，计算机导致了劳动力市场职业结构的转变。例如，Autor和Dorn（2013）表明，随着计算机化侵蚀了执行日常任务的劳动力的工资，工人将把他们的劳动力供应重新分配给技能相对较低的服务职业。更具体地说，在1980年至2005年间，美国服务业的劳动时间份额在前三十年持平或下降后增长了30%。此外，美国就业的净变化在技能水平上呈U形，这意味着最低和最高就业技能四分位数急剧扩大，中间的相对就业下降。

The Computer Revolution can go some way in explaining the growing wage inequality of the past decades. For example, Krueger (1993) finds that workers using a computer earn roughly earn 10 to 15 percent more than others, but also that computer use accounts for a substantial share of the increase in the rate of return to education. In addition, more recent studies find that computers have caused a shift in the occupational structure of the labour market. Autor and Dorn (2013), for example, show that as computerisation erodes wages for labour performing routine tasks, workers will reallocate their labour supply to relatively low-skill service occupations. More specifically, between 1980 and 2005, the share of US labour hours in service occupations grew by 30 percent after having been flat or declining in the three prior decades. Furthermore, net changes in US employment were U-shaped in skill level, meaning that the lowest and highest job-skill quartile expanded sharply with relative employment declines in the middle of the distribution.

高技能就业的扩大可以解释为通过计算机执行日常任务的价格下降，这是对更抽象和创造性服务的补充。从生产函数的角度来看，日常信息投入供应的向外转移会增加所需工人的边际生产力。例如，文本和数据挖掘提高了法律研究的质量，因为不断获取市场信息提高了管理决策的效率，即由收入分配高端的技术工人执行的任务。其结果是劳动力市场两极分化加剧，高收入认知工作和低收入体力工作的就业人数不断增加，同时中等收入日常工作也被掏空。这种模式并非美国独有，同样适用于许多发达经济体（Goos等人，2009年）。

The expansion in high-skill employment can be explained by the falling price of carrying out routine tasks by means of computers, which complements more abstract and creative services. Seen from a production function perspective, an outward shift in the supply of routine informational inputs increases the marginal productivity of workers they are demanded by. For example, text and data mining has improved the quality of legal research as constant access to market information has improved the efficiency of managerial decision-making – i.e. tasks performed by skilled workers at the higher end of the income distribution. The result has been an increasingly polarised labour market, with growing employment in high-income cognitive jobs and low-income manual occupations, accompanied by a hollowing-out of middle-income routine jobs. This is a pattern that is not unique to the US and equally applies to a number of developed economies (Goos, et al., 2009).

21世纪的技术进步将如何影响劳动力市场的结果，还有待观察。纵观历史，技术进步极大地改变了就业构成，从农业和手工艺品商店，到制造业和职员，再到服务业和管理业。然而，事实证明，对技术失业的担忧被夸大了。这种担忧没有实现的明显原因与 Ricardo 关于机械的著名章节有关，该章节认为节省劳动力的技术减少了对无差别劳动力的需求，从而导致了技术失业（Ricardo，1819）。然而，正如经济学家长期以来所理解的那样，一项用机器取代工人的发明将对所有产品和要素市场产生影响。生产效率的提高降低了一种商品的价格，将增加实际收入，从而增加对其他商品的需求。因此，简而言之，技术进步对就业有两个相互竞争的影响（Aghion和Howitt，1994）。首先，作为劳动力的技术替代品，存在破坏效应，要求工人重新分配劳动力供应；其次，还有资本化效应，因为越来越多的公司进入生产率相对较高的行业，导致这些行业的就业人数增加。

How technological progress in the twenty-first century will impact on labour market outcomes remains to be seen. Throughout history, technological progress has vastly shifted the composition of employment, from agriculture and the artisan shop, to manufacturing and clerking, to service and management occupations. Yet the concern over technological unemployment has proven to be exaggerated. The obvious reason why this concern has not materialised relates to Ricardo’s famous chapter on machinery, which suggests that laboursaving technology reduces the demand for undifferentiated labour, thus leading to technological unemployment (Ricardo, 1819). As economists have long understood, however, an invention that replaces workers by machines will have effects on all product and factor markets. An increase in the efficiency of production which reduces the price of one good, will increase real income and thus increase demand for other goods. Hence, in short, technological progress has two competing effects on employment (Aghion and Howitt, 1994). First, as technology substitutes for labour, there is a destruction effect, requiring workers to reallocate their labour supply; and second, there is the capitalisation effect, as more companies enter industries where productivity is relatively high, leading employment in those industries to expand.

尽管资本化效应在历史上一直占主导地位，但正如凯恩斯（1933）所指出的，我们发现的节约劳动力使用的方法可能超过我们发现劳动力新用途的速度。人类劳动占主导地位的原因与其通过教育采用和获得新技能的能力有关（Goldin和Katz，2009）。然而，随着计算机化进入更多的认知领域，这将变得越来越具有挑战性（Brynjolfsson 和 McAfee，2011）。因此，最近的实证研究结果尤其令人担忧。例如，Beaudry等人（2013）记录了过去十年对技能的需求下降，尽管受过高等教育的工人的供应持续增长。它们表明，高技能工人已经从职业阶梯上往下走，从事传统上由低技能工人从事的工作，将低技能工人进一步推向职业阶梯，在某种程度上甚至脱离了劳动力队伍。这引发了以下问题：（a）人类劳动通过教育赢得与技术竞争的能力；以及（b）技术失业的潜在程度，因为技术进步速度的加快将导致更高的工作人员流动，从而导致更高自然失业率（Lucas和Prescott，1974；Davis和Haltiwanger，1992年；Pissarides，2000年）。虽然目前的研究仅限于研究技术的破坏效应，但它提供了一个有用的指标，表明未来几十年平衡面临风险的工作所需的就业增长。

Although the capitalisation effect has been predominant historically, our discovery of means of economising the use of labour can outrun the pace at which we can find new uses for labour, as Keynes (1933) pointed out. The reason why human labour has prevailed relates to its ability to adopt and acquire new skills by means of education (Goldin and Katz, 2009). Yet as computerisation enters more cognitive domains this will become increasingly challenging (Brynjolfsson and McAfee, 2011). Recent empirical findings are therefore particularly concerning. For example, Beaudry, et al. (2013) document a decline in the demand for skill over the past decade, even as the supply of workers with higher education has continued to grow. They show that high-skilled workers have moved down the occupational ladder, taking on jobs traditionally performed by low-skilled workers, pushing low-skilled workers even further down the occupational ladder and, to some extent, even out of the labour force. This raises questions about: (a) the ability of human labour to win the race against technology by means of education; and (b) the potential extent of technological unemployment, as an increasing pace of technological progress will cause higher job turnover, resulting in a higher natural rate of unemployment (Lucas and Prescott, 1974; Davis and Haltiwanger, 1992; Pissarides, 2000). While the present study is limited to examining the destruction effect of technology, it nevertheless provides a useful indication of the job growth required to counterbalance the jobs at risk over the next decades.

由于Bilibili字数限制，完整版已放在 Github
https://github.com/soryu-ryouji/Don_Quixote_Project