2019年经济学一等奖

United States President Donald Trump recently voiced the concerns of many citizens when he proclaimed, “Illegal immigration hurts American workers; burdens American taxpayers; and . . . costs our country billions and billions of dollars each year.”[1] Similar sentiments are expressed in the United Kingdom, where native workers fear the “Polish plumber,”[2] and in Australia, where Australian Labor Party leader, Bill Shorten, warns that work visas “undercut local jobs, wages and conditions.”[3] At first glance, it may seem reasonable to conclude that, with a fixed number of jobs available, immigrants present a threat to native workers. However this Malthusian logic incorrectly assumes immigrants are perfect substitutes for locals and that the demand for labor is static.

Recent empirical work demonstrates that firms, workers, and markets are dynamic and able to adapt to an expanded workforce.[4] While large-scale immigration may have distributional implications, there is little evidence to support claims that, on a macro level, immigration depresses wages, drives up unemployment, or burdens taxpayers.[5] In fact, economic theory and empirical studies demonstrate that in the long run immigration raises productivity, wages, and living standards.[6] At the global level, researchers estimate that the removal of all barriers to labor mobility would double world GDP.[7] Staggering gains of this order suggest that international immigration policy deserves careful consideration.

Immigration is a complex and emotion-charged matter, but any serious examination of this issue must be grounded in fact. Fortunately, existing economic literature provides the empirical evidence and the analytical framework to rationally examine the issue, starting with the impetus behind approximately 260 million[8] immigrants in the world today and another 750 million[9] who would move permanently to another country if given the opportunity. In his seminal work first published in 1932, Nobel Laureate John Hicks posits, “Differences in net economic advantages, chiefly differences in wages, are the main cause of migration.”[10] In 1987 Harvard economist George Borjas employed a selection model, based on the work of Andrew Roy, to demonstrate that potential migrants consider relative return to skill and skill transferability in addition to relative income levels.[11]

Individuals weigh the benefits of emigrating against the often-significant costs and barriers presented by such an endeavor. For instance, policy in the host country may target specific individual attributes or restrict the total number of immigrants. Legal immigrants must pay passport, visa, and transportation fees. Undocumented migrants who seek illicit entry may pay a smuggler or incur significant physical risk. Once inside the host country, new immigrants may lack the local network, credentials, or labor market expertise needed to find suitable employment in a timely manner. There are also psychic costs that may arise from the language barrier, unfamiliar cultural norms, and social isolation.

Despite these challenges, the potential productivity gains from migration are significant. In a perfectly competitive labor market, each worker is paid a wage commensurate with the value he produces. Migration allows workers to seek higher wages by moving to a location where they are more productive. This yields a more efficient allocation of labor that economists estimate is worth as much as 130 trillion dollars in additional global output.[12] If even 5% of the world’s poorest were to migrate to developed nations, the increase in world GDP would be greater than the increase from the complete elimination of all international barriers to the movement of goods, services, and capital flows.[13] Yet, in spite of the potential gains, nearly every developed country places restrictions on immigration.[14]

One factor driving these restrictions is that many presume immigrants depress natives’ wages.[15] However in practice, because of differences in language, vocational, and technical skills, most immigrant workers are not close substitutes for native workers and, therefore, do not compete for the same jobs.[16] In fact, immigrants often are complements in production, rather than substitutes. In an oft-cited paper, economists Giovanni Peri and Chad Sparber, present a dynamic process where natives respond to an influx of immigrants by shifting into jobs that leverage their comparative advantage.[17] This occurs across the education spectrum; less-educated natives respond to an increase in less-educated immigrants by shifting from manual-intensive to communication-intensive jobs, and college-educated natives move into managerial roles when high-skilled engineers and scientists enter the country.[18]

Of course, the gains from immigration are not evenly distributed. Harvard economist George Borjas grouped U.S. workers into skill cells based on their education and experience. Borjas found that, within certain skill cells, immigration has a statistically significant negative impact on weekly earnings, particularly among the less educated.[19] Studies in Canada, Germany, and Norway yielded similar results.[20] Although the skill cells technique does not capture the possible benefits to natives who change their skill sets over time in response to immigration, it does offer empirical evidence that in the short run weekly earnings of less-educated natives are hurt by an inflow of immigrants with similar skills.

However in the long run overall wages will rise with productivity, and studies show a positive relationship between immigration and productivity gains. High-skilled immigrants attract capital investment and foster innovation, both of which boost labor productivity.[21] Less-skilled immigrant workers, such as landscapers and childcare providers, encourage more high-skilled natives, especially women, to enter the workforce.[22] Immigrants who are investors or entrepreneurs boost native employment and expand the set of available goods and services.[23] And because immigrants have knowledge of the available products, business norms, and regulations in their home country, they are able to facilitate welfare improving international trade by lowering transaction costs[24] and providing greater product variety.[25]

In addition to concerns about the labor market, many citizens of developed countries harbor fear that immigrants are a burden to native taxpayers.[26] However, here too the evidence suggests that such concerns may be unfounded. Estimates of immigration’s fiscal impact vary but a survey of the relevant literature reveals a number of clear patterns. To begin with, the fiscal impact of immigration tends to be positive and relatively small.[27] For example, a comprehensive study undertaken by the Organization for Economic Cooperation and Development, using static accounting in 2013, found that in twenty out of the twenty-seven member nations studied, the net fiscal contribution by immigrants was between zero and 0.5% of GDP.[28] In general, empirical studies show a greater positive net fiscal impact in countries with more highly skilled immigrants and a lower or even negative impact in countries with large humanitarian immigrant inflows.[29] Younger immigrants tend to have a more positive fiscal impact because they are healthier, participate in the labor force longer, and assimilate more successfully than older immigrants.[30]

The benefits of migration extend to the sending country as well. The most direct benefit comes from remittances which, according to the World Bank, often exceed total foreign aid and, in nine countries, account for more than 20% of GDP.[31] Furthermore, although early research from distinguished economists such as Jagdish Bhagwati and Koichi Hamada warned of dire consequences for origin countries losing highly skilled immigrants—so-called brain drain—the data show these fears to be largely unfounded provided emigration rates do not exceed 35%.[32] Brain drain fails to materialize because, in addition to cash payments and investments, high-skilled emigrants return expertise and institutional reform to the sending country.[33] Furthermore, the mere prospect of emigration incents the population, only a fraction of whom will ultimately leave, to attain greater levels of education and training.[34] All these factors raise total factor production and living standards in the sending country.[35]

Despite the benefits for both the origin and host countries, constructing fair and effective immigration policy is a complicated normative process that must allow for historical, political, and social considerations. As such, current immigration policy varies greatly across the globe from family-based policy in the United States to point-based systems in Australia to guest worker programs in the United Arab Emirates. Family-based immigrants tend to have lower earnings at entry but experience faster wage growth because of better social networks and greater incentive to acquire locally valued human capital.[36] Point-based systems favor immigrants with specified characteristics such as education, occupation, or language skills. These systems result in more high-skilled immigrants but often these skills do not transfer well to the host country, and the criteria may not be flexible enough to keep pace with the dynamic needs of an ever-changing business environment. Guest worker programs offer greater flexibility to meet labor shortages and may discourage illegal immigration, but workers typically return home after a specified period of time and have limited access to social services.[37]

Every policy has relative strengths and each situation is unique, but there are proven measures host nations may take to enhance immigrants’ odds of success, beginning with language training. Language skills are critical, and immigrant-focused language programs lead to greater economic success and social integration.[38] Active labor market programs, such as job search assistance and counseling, workplace introduction, and on-going mentoring, increase employment rates for immigrants.[39] Lastly, immigrants tend to achieve greater success in countries with flexible labor markets and effective anti-discrimination law.[40]

Sound policy must also account for the native workers negatively impacted by immigration, especially older and less-educated individuals.[41] This is a particularly vulnerable group and many government run programs designed to retrain and re-employ this cohort are ineffective.[42] However programs that leverage the power of the private sector are often more successful. For example, Swedish industries and unions jointly established the Job Security Councils,[43] and in Germany the Federal Employment Agency provides vouchers to cover the cost of privately run retraining and job placement services.[44] These programs are more effective because they better identify the skills most in demand and more quickly adjust to changes in the economic environment.[45]

Although economic models predict monumental gains from unrestricted international labor mobility, this is not politically feasible in the near term. An incremental approach to such a grand, and largely irreversible, endeavor is more pragmatic. That said, there is a compelling argument for immigration policy driven by market forces rather than bureaucratic rules. An example of such an approach, first proposed by Nobel Laureate Gary Becker, calls for the daily sale of a set number of visas in an open market, at a price determined by the laws of supply and demand.[46] Economist Benjamin Powell proposes the annual sale of 5 immigrant visas for permanent residency per 1,000 of host country population.[47] The cost of the visa may be paid by the immigrant worker, the employer, or a third party such as a charitable foundation. Payment could be financed with a traditional loan or even an Income Share Agreement.[48]

A market-based approach may be more politically feasible because it attracts immigrants with more productive and entrepreneurial potential, and visa payments contribute to government revenue.[49] It is arguably more fair than existing policy because entry into the country is not determined by family ties, country of origin, inflexible point-based systems, or other Byzantine regulation. Market-based policy could be augmented with a procedure that allows current undocumented workers to purchase a visa, in the open market, after successful completion of a non-trivial amnesty program. In some cases the needs of a nation may be better served by selling two types of visas, permanent and seasonal, in the open market or by making a relatively small number of free visas available to refugees from political or religious persecution. However, regardless of the particulars, free markets depend on the rule of law,[50] and therefore successful market-based policy must—some might say regrettably―include credible and sufficiently harsh consequences for illegal immigrants and their employers.

A robust body of empirical analysis over the last several decades challenges the notion that immigrants, in aggregate, undermine local labor markets or strain government budgets. Rather, the data suggest that in the long run immigration raises living standards for natives as well as immigrants. A further reduction in barriers to international labor mobility could add tens of trillions of dollars to global GDP.[51] Although immigration is often an emotional and politically contentious issue, potential immigrants and future generations deserve thoughtful policy based on sound principles and empirical evidence, not knee-jerk reactions and political pandering.

Footnotes

1 Donald Trump, “Remarks by President Trump on the Illegal Immigration Crisis and Border Security,” The White House, Roosevelt Room, Washington DC, November 1, 2018, https://www.whitehouse.gov/.

2 Daniel Pimlott, “Migration: Why we need Polish plumbers,” Financial Times, February 22, 2006, https://www.ft.com/.

3 William Richard Shorten, “Protecting Local Workers – Restoring Fairness to Australia's Skilled Visa System,” Bill’s Media Releases, April 23, 2019, https://www.billshorten.com.au/.

4 Giovanni Peri, “Do Immigrant Workers Depress the Wages of Native Workers?” IZA World of Labor, (May 2014), 2.
5 Benjamin Powell, The Economics of Immigration: Market-Based Approaches, Social Science, and Public Policy (New York: Oxford University Press, 2015), 11-70.
6 Giovanni Peri, “Do Immigrant Workers Depress the Wages of Native Workers?” IZA World of Labor, (May 2014), 1.
7 Michael A. Clemens, “Economics and emigration: Trillion-dollar bills on the sidewalk?” Journal of Economic Perspectives 22, no. 3 (2011), Table 1.

8 United Nations, Department of Economic and Social Affairs, Population Division, International Migration Report 2017: Highlights, (New York, 2017) Table 1, https://www.un.org.

9 Neli Esipova, Anita Pugliese, and Julie Ray, “More Than 750 Million Worldwide Would Migrate If They Could,” Gallop, (December 10, 2018), https://news.gallup.com/

10 John R. Hicks, The Theory of Wages, 2nd ed. (London: Macmillan, 1963), 76.
11 George J. Borjas, “Self-selection and the Earnings of Immigrants,” American Economic Review 77, no. 4 (1987): 551-52.

12 Michael A. Clemens, “Economics and emigration: Trillion-dollar bills on the sidewalk?” Journal of Economic Perspectives 22, no. 3 (2011), Table 1.

13 Benjamin Powell, The Economics of Immigration: Market-Based Approaches, Social Science, and Public Policy (New York: Oxford University Press, 2015), 2.

14 Ibid., 11.

15 Giovanni Peri, “Do Immigrant Workers Depress the Wages of Native Workers?” IZA World of Labor, (May 2014), 2.

16 Ibid., 8.

17 Giovanni Peri and Chad Sparber. “Task Specialization, Immigration and Wages.” American Economic Journal 1, no. 3 (2009): 135-69.

18 Gianmarco I. P. Ottaviano and Giovanni Peri, “Rethinking the Effect of Immigration on Wages.” Journal of the European Economic Association 10, no. (2012): 191.

19 George J. Borjas, “The Labor Demand Curve is Downward Sloping: Reexamining the Impact of Immigration on the Labor Market,” Quarterly Journal of Economics 118, no. 4 (2003): 1346-48.

20 Cynthia Bansak, Nicole B. Simpson, and Madeline Zavodny, The Economics of Immigration, (London and New York: Routledge, 2015), 183.

21 Cynthia Bansak, Nicole B. Simpson, and Madeline Zavodny, The Economics of Immigration, (London and New York: Routledge, 2015), 188-204.

22 Patricia Cortes and Jose Tessada, “Low-Skilled Immigration and the Labor Supply of Highly Skilled Women,” American Economic Journal Applied Economics 3, no. 3 (July 2011): 110-11.

23 Jennifer Hunt, “Which Immigrants Are Most Innovative and Entrepreneurial? Distinctions by Entry Visa,” Journal of Labor Economics 29, no. 3 (2011): 419-22.

24 Cynthia Bansak, Nicole B. Simpson, and Madeline Zavodny, The Economics of Immigration, (London and New York: Routledge, 2015), 201-02.

25 Chen Bo and David S. Jacks, “Trade, Variety, and Immigration,” Economics Letters 117, no. 1 (March 2012): 243-46, doi:10.1016/j.econlet.2012.04.007.

26 Giovanni Peri, “Do Immigrant Workers Depress the Wages of Native Workers?” IZA World of Labor, (May 2014), 2.

27 Cynthia Bansak, Nicole B. Simpson, and Madeline Zavodny, The Economics of Immigration, (London and New York: Routledge, 2015), 232.

28 Organization for Economic Cooperation and Development, International Migration Outlook 2013 (Paris: OECD Publishing, 2013), doi.org/10.1787/migr_outlook-2013-en.

29 Cynthia Bansak, Nicole B. Simpson, and Madeline Zavodny, The Economics of Immigration, (London and New York: Routledge, 2015), 230-32.

30 Ibid., 230-34.

31 World Bank, Global Economic Prospects 2006 : Economic Implications of Remittances and Migration, (Washington DC: World Bank, 2006), 85-127.

32 Frederic Docquiera and Hillel Rapoport, “Quantifying the Impact of Highly-Skilled Emigration on Developing Countries,” Centre for Economic Policy Research (May 16, 2009): 77.

33 World Bank, Global Economic Prospects 2006 : Economic Implications of Remittances and Migration, (Washington DC: World Bank, 2006), 25-72.

34 Michael Beine, Frederic Docquier, and Hillel Rapoport, "Brain drain and human capital formation in developing countries: winners and losers," Economic Journal 118, no. 4 (2008): Table 1.

35 Benjamin Powell, The Economics of Immigration: Market-Based Approaches, Social Science, and Public Policy (New York: Oxford University Press, 2015), 23-31.

36 Cynthia Bansak, Nicole B. Simpson, and Madeline Zavodny, The Economics of Immigration, (London and New York: Routledge, 2015), 281-324.

37 Ibid., 313-318.

38 Barry Chiswick and Paul Miller, Handbook of the Economics of International Migration, Volume 1A: The Immigrants (Oxford: Elsevier, 2015), 213-70.

39 Ulf Rinne, “The Evaluation of Immigration Policies,” IZA Discussion Paper 6369 (February 2012): 19-20.

40 Cynthia Bansak, Nicole B. Simpson, and Madeline Zavodny, The Economics of Immigration, (London and New York: Routledge, 2015), 167, 325.

41 Ronald D'Amico and Peter Z. Schochet, The Evaluation of the Trade Adjustment Assistance Program: A Synthesis of Major Findings, Prepared for U.S. Department of Labor, Employment and Training Administration. (Oakland, CA: Social Policy Research Associates and Princeton, NJ: Mathematica Policy Research, December 2012) iv..https://www.mathematica-mpr.com/.

42 Jeffrey Selingo, “The False Promises of Worker Retraining,” The Atlantic, January 8, 2018, https://www.theatlantic.com/.

43 Thomas K. Grose, “The Worker Retraining Challenge,” U.S. News and World Report, February 6, 2018, https://www.usnews.com/.

44 Julia Lang and Thomas Kruppe, “Labour Market Effects of Retraining for the Unemployed - the Role of Occupations,” German Economic Association Conference Paper, (August 2014): 26. http://hdl.handle.net/10419/100420.

45 Council of Economic Advisers. Addressing America’s Reskilling Challenge. (July 2018): 22. https://www.whitehouse.gov/.

46 Benjamin Powell, The Economics of Immigration: Market-Based Approaches, Social Science, and Public Policy (New York: Oxford University Press, 2015), 146-54.

47 Benjamin Powell, The Economics of Immigration: Market-Based Approaches, Social Science, and Public Policy (New York: Oxford University Press, 2015), 147.

48 Ibid.,152

49 Robert W. Fairlie, Kauffman Index of Entrepreneurial Activity, 1996-2011 (Kansas City, MO: Kauffman Foundation, 2013), 10-13.

50 Samuel Bufford, “International Rule of Law and the Market Economy - An Outline,” Southwest Journal of Law and Trade in the Americas 12, (2006): 311.

51 Michael A. Clemens, “Economics and emigration: Trillion-dollar bills on the sidewalk?” Journal of Economic Perspectives 22, no. 3 (2011), 87.

Author’s Note

Unless specified otherwise, this paper will use the word “immigrants” to denote individuals who are not born a citizen of the country where they currently reside. This includes voluntary and humanitarian immigrants, who enter the host country with or without proper documentation, and stay on a temporary or permanent basis.

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