This is not because markets are morally superior, though they do require freedom of choice to function effectively. Markets are tools that, relative to the alternatives, happen to have great strengths with respect to incentives, efficiency, and innovation. But they are not perfect; they underperform in the presence of externalities (the un-priced consequences – for example, air pollution – of individual actions), informational gaps and asymmetries, and coordination problems when there are multiple equilibria, some superior to others.
But markets have more fundamental weaknesses. Or, rather, most societies have important economic and social objectives that markets and competition are not designed to achieve. In today’s rapidly globalizing world, the most important of these objectives – expressed in various ways through the political and policymaking process in a wide range of countries – are stability, distributional equity, and sustainability.
Consider stability. We live in a world of largely decentralized networks of increasing complexity: electronic networks, networks of supply chains and trade, financial networks that link the balance sheets of disparate entities. Market incentives cause actors to operate or modify parts of the network in ways that maximize efficiency locally. But the presumption – often an article of faith – that the whole remains stable and resilient has no theoretical or empirical support. Indeed, it seems inaccurate.
For example, it has been known for some time that networks that are efficient are often not resilient, because resilient networks have inefficient redundancies. Resilience is a public good, created by the right kind of redundancy.
In a decentralized structure, redundancy tends to be undersupplied in the process of local optimization. That is why the tsunami that hit Japan last year disrupted many global supply chains: they were (and still are) too efficient from the standpoint of withstanding shocks.
In financial markets, local optimization seems to lead to excessive leverage and other forms of risk-taking that undermine the stability of the system. Much research is needed to understand which interventions or restrictions on individual choice are needed to make certain kinds of market equilibria stable. But, clearly, markets do not do this well by themselves.
Consider, next, how labor-saving technological change and the integration of several hundred million new workers into global markets have affected income distribution, returns to education, and employment opportunities almost everywhere. In particular, the share of national income going to capital and human capital (highly educated people) is rising on a broad front, fueling increasing concentration of wealth.
Even so, income distributions vary widely among the developed countries. For example, in the US, the top 20% earns, on average, 8.4 times more than the bottom 20%. In the UK, the same ratio is 7.2, and it is only 4.3 in Germany (compared to a whopping 12.2 in China). These differential outcomes reflect distinctive combinations of market forces and social contracts.
Income distributions are influenced by taxation and fiscal policy, which usually have redistributive effects, directly and through the provision of social services and insurance. But these distributions are also affected by policies and investments that focus on the supply side, and that produce education and skills that match (or don’t match) a rapidly evolving global structure of labor demand.
Part of the challenge is that demand for labor moves to supply, rather than vice versa, because labor mobility in the global economy is limited. To assume a constant level and composition of labor demand would be as mistaken as taking current passenger demand as a fixed reference point in planning public-transportation systems. In this and other cases, supply influences demand over time (Steve Jobs, for example, understood this better than most).
That is why it is crucial to think about potential demand in tackling this kind of matching problem. As with stability, markets cannot be relied upon to deal effectively with this problem on their own. Public policy and public-sector investment matter, too.
Attention is increasingly – and, in my view, rightly – being focused on the role of the state, and in particular on the state’s balance sheet. Experience in developing and advanced countries alike suggests that states with substantial and healthy balance sheets are better positioned to deal with today’s stability, distributional, and sustainability challenges. The benefits are several, including an ability to withstand shocks and mount countercyclical responses, as well as a capacity to recycle income to households during periods like the present, when the share of income that goes to capital is rising (with adverse distributional consequences).
In addition, countries periodically need to be able to mount and sustain public-sector investment in technology, or to engage in risk-sharing, in order to adapt to shifting competitive conditions or respond to shocks. Minority public ownership can provide resources, while retaining the benefits of competition, and ensure that some of the returns accrue to the general public via government revenues.
Some of this will run counter to existing orthodoxy, and may provoke a healthy debate. A relatively narrow focus on efficiency and growth, at least in many advanced countries, may have worked in the early decades after WWII, when distributional patterns were benign and instability rare. Today that is not enough. Stability, equity, and sustainability challenges have become crucially important, and the role of the state in relation to markets may need re-thinking as a result.
Re-orienting policy frameworks to longer time horizons, with a more balanced and forward-looking focus on stability and equity (without losing sight of efficiency and innovation), seems essential to meeting the needs, hopes, and expectations of people everywhere. Indeed, that is the key to addressing sustainability, to which I will turn next month.
Michael Spence, a Nobel laureate in economics, is Professor
of Economics at New York University’s Stern School of Business, Distinguished
Visiting Fellow at the Council on Foreign Relations, and Senior Fellow at the
Hoover Institution, Stanford University. His latest book is The Next
Convergence – The Future of Economic Growth in a Multispeed World (www.thenextconvergence.com).
Michael Spence: 理智戰勝市場
米蘭—— 自二戰結束以來的66年裡，實際上所有中央集權的計劃經濟都消失了，主要原因是低效和低增長。如今，市場、價格信號、分散管理、刺激措施以及回報驅動的投資幾乎是各地資源分配的特征。
這並不是因為市場在道德上更勝一籌，盡管市場需要自由選擇才能有效運行。與其他工具相比，市場工具在刺激措施、效率和創新方面正好擁有巨大的優勢。但是市場並不完美，當面臨外部影響（個人行動所帶來的無法計價的后果——比如，空氣污染）、信息差距和不對稱性以及協調問題（當有多項平衡，一些平衡比另一些平衡更重要時）時，市場就會表現不佳。
但是市場有更加根本性的弱點。具體點說，大多數社會都有重要的經濟和社會目標，而市場和競爭並不是為了實現這些目標。在當今快速全球化的世界裡，其中最重要的目標——各國在政治和決策過程中都有不同的表述——是穩定、分配公平和可持續性。
先談一下穩定。我們生活在一個網絡基本上分散但日益復雜的世界裡：電子網絡、供應鏈和貿易網絡以及連接不同實體資產負債表的金融網絡。市場的刺激促使當事人因地制宜最大限度地提高效率，運營網絡或改進部分網絡。但是假設——通常是一種信仰——是總體而言仍然是穩定的，恢復力沒有理論和經驗依據。實際上，這似乎不准確。
比如，高效的網絡常常沒有恢復力，原因是有恢復力的網絡有過剩現象，效率不高，人們知道這一點已經有一段時間了。恢復力是對大家都有利的東西，適當的剩余量創造了恢復力。
在分散的結構中，在局部最優化過程中，剩余量往往供應不足。這就是去年海嘯襲擊日本破壞了許多全球供應鏈的原因：就承受沖擊而言，它們以前太高效了，現在仍然是如此。
在金融市場上，局部最優化似乎會導致過度杠杠化和其他形式的冒險行為，破壞金融系統的穩定性。為了使這類市場平衡穩定，要知道對個人的選擇採取那類干預措施或限制措施尚需大量研究。但是，清楚的是市場自身無法做好這一點。
接下來看一下節省勞動力的技術變革以及數億新工人融入全球市場是如何影響各地的收入分配、教育回報以及就業機會的。尤其是，國民收入投資資本和人力資本（受過良好教育的人）的比重正在大幅增加，助長財富日益集中。
即便如此，各發達國家的收入分配也大不相同。比如，在美國，頂層20%的平均收入是底層20%的8.4倍。在英國，這一數字為7.2倍，在德國隻有4.3倍（在中國則高達12.2倍）。這些不同的結果反映出市場力量和社會契約獨特的組合。
收入分配受到稅收和財政政策的影響，稅收和財政政策常常通過提供社會福利和保險直接起到重新分配的作用。但是這些分配還受到政策和投資的影響，政策和投資主要關注的是供應方並能催生與快速演化的全球勞動力需求結構匹配（或不匹配）的教育和技能。
部分挑戰是勞動力供不應求而不是供過於求，這是因為全球經濟環境下的勞動力流動是受到限制的。與拿當前的客流量作為公共交通系統規劃的固定參照點一樣，制定固定的勞動力需求水平和組成成分也是錯誤的。在這個以及其他問題上，隨著時間的推移，供應會影響需求（比如，史蒂夫•喬布斯對這點的理解比大多數人都深刻）。
這就是考慮解決這類匹配問題潛在需要至關重要的原因。至於穩定問題，不要依賴市場自身能夠有效地解決它。公共政策和公共部門的投資也至關重要。
人們的注意力日益集中到國家的作用上，尤其是國家的資產負債表上，在我看來，這是對的。發展中國家和發達國家的經驗都表明，擁有大量良好資產負債表的國家能夠更好的應對如今的穩定性、分配和可持續性的挑戰。有不少好處，其中包括承受沖擊和作出反周期反應的能力以及在投資資本的收入比重不斷增加（對分配不利）時期，比如說現在，將收入返還到家庭手中的能力。
此外，各國需要定期增加和維持公共部門對技術的投資，或者共擔風險，以便適應變化的競爭環境或應對沖擊。在獲取競爭好處的同時，少量國有企業可以提供資源並確保通過政府的收入，普通民眾能夠增加部分收入。
其中的一些東西與現存的正統說法沖突，可能會引發一場良性的激辯。相對狹隘地關注效率和經濟增長可能在二戰后的前幾十年發揮了作用（至少在許多發達國家是如此），這段時間分配方式良好，較穩定。如今，這樣已經不夠了。穩定、公平和可持續性的挑戰已經變得非常重要，因此與市場相關的國家作用可能需要重新考慮。
重新調整政策框架著眼於更加長遠的未來，以更加平衡和前瞻性的眼光關注穩定和公平（同時兼顧效率和創新），這似乎對於滿足各地人民的需要、希望和期待來說必不可少。實際上，這是解決可持續性問題的關鍵，下個月我將討論這個問題。
Michael
Spence，曾獲諾貝爾經濟學獎、現任紐約大學斯特恩商學院經濟學教授、美國對外關系委員會傑出訪問學者、斯坦福大學胡佛研究所高級研究員，最近著有《下一次趨同——多速世界經濟增長的未來》一書。