数字时代要求反思竞争理论
对美国(和其他地方)经济竞争格局健康状况的焦虑正在加剧。这些担忧或许有理有据，但如果要采取有力举措，就需要经济学家们拿出一些切实可行的方式，来证明和衡量数字经济中日益增强的市场支配力造成的危害。
The forces driving concentration do not affect the US alone. In all digital markets, the cost structure of high upfront costs and low additional or marginal costs means there are large economies of scale. The broad impact of digital technology has been to increase the scope of the markets many businesses can hope to reach.
推动集中化的力量并非只影响美国。在所有的数字市场中，高前期成本和低附加/边际成本的成本结构意味着，存在着较大的规模经济。数字技术的整体影响是扩大了许多企业能够企及的市场范围。
In pre-digital days, the question an economist would ask is whether the efficiencies gained by big or merging companies would be passed on to consumers in the form of lower prices. Another key question was whether it would still be possible for new entrants to break into the market.
在前数字时代，经济学家提出的问题是，大企业或者正在合并的企业提高的效率，是否会以降低价格的形式传递给消费者?另外一个关键问题是，新入行者是否还有可能进入市场?
Digital platforms make these questions harder to answer. The basic economic theory, developed by Jean Tirole and others, establishes that in such markets one “side” will cross-subsidise the other. So the signal prices send about competition is completely different from in a traditional market. Platforms also generally expand into neighbouring markets, so the standard market definition exercises done by competition authorities are doubly uninformative.
数字平台使这些问题变得更难以回答。按照让•梯若尔(Jean Tirole)等人发展出的基本经济理论，在数字时代的市场中，一“侧”将对另一侧形成交叉补贴。因此，在这类市场上，价格传递的有关竞争的信号与传统市场截然不同。数字平台通常还会扩张进入邻近市场，因此竞争管理当局定义标准市场的做法更加缺乏依据。
Big digital companies argue that the consumer benefit they provide through free services is immense. So where is the harm? 数字领域的大公司主张，它们通过免费服务提供了巨大的消费者福利，那么危害在哪里?
They rely heavily too on competition among themselves, and the threat of digital disruption: just as Facebook quickly toppled MySpace, so it could be toppled in turn. They argue that competition for the market is intense, and some competition experts agree.
这些公司还非常依赖相互之间的竞争，以及数字颠覆的威胁：就如Facebook迅速颠覆了MySpace，Facebook本身也可能被颠覆。这些公司提出，数字市场竞争激烈，一些竞争专家也认同这一点。
This might be right, but we do not know. Economists are letting down competition regulators in failing to provide the tools for evaluating in specific cases the claim that — in a world of significant returns to scale and network effects — bigger is better for everyone.
这种说法或许正确，但我们不得而知。经济学家们正使竞争管理当局感到失望，因为他们拿不出在具体个案中评判如下主张的工具：在规模和网络效应获得丰厚回报的世界，更大对每一个人都更好。
One much-needed tool is how to assess consumer benefits. 我们亟需的一件工具是消费者福利的评估方法。
Google and Facebook provide services consumers greatly value without taking money directly from them; but advertisers place great value on the services too, and their payments will be passed on ultimately to consumers in the price of whatever is being advertised. How high is that price? The network effects of digital platforms do produce real economic welfare gains, but nobody knows how big these are or who captures them.
谷歌(Google)和Facebook提供消费者非常重视的服务，并且没有从消费者那里直接收取费用;但广告商也非常重视这些服务，它们为这些服务支付的费用最终将以广告产品或服务的价格的形式转嫁给消费者。这个价格有多高?数字平台的网络效应的确会产生真正的经济福利，但没人知道这些经济福利有多大，也没人知道谁获得了这些福利。
A second issue is how to take into account the interactions between markets, given that most platforms and tech companies steadily expand into other activities and markets. There has probably been too little focus in antitrust policy for a long time on the purchasing power of big companies.
第二个问题是如何考虑市场的相互作用，考虑到大多数数字平台和科技公司正稳步扩张进入其他活动和市场。长期以来，反垄断政策对大公司购买力的关注很可能太少了。
A third issue, perhaps the most important, is the effect increasing concentration has on incentives to innovate and invest. The economic welfare gains from innovation will usually dwarf the gains from lower prices. Competition economics has always been poor at trying to quantify these relative gains, but the stakes are high now that innovation is seen as one of the main drivers of competition. How can potential challengers develop new technologies to topple an incumbent if they have to compete with an apparently zero price? For that matter, how will investment in physical networks or content get funded if an incumbent using the network and content captures all the profit downstream?
第三个，或许也是最重要的一个问题是，集中化程度提高对创新和投资的激励力量有什么影响?创新带来的经济福利通常会超过降低价格带来的经济福利。竞争经济学一直无法很好地在量化这一差值，但既然创新被视为竞争的主要推动力之一，这个差值就涉及重大利害关系。如果潜在的挑战者不得不与貌似为零的价格竞争，他们怎么研发新技术来推翻现有企业?而且，如果现有企业利用网络和内容捕获了所有下游利润，如何获得资金投资于物理网络或者内容?
Reversing the kind of increased concentration seen in the US takes a significant commitment of political capital and bureaucratic energy. These are more likely to be forthcoming if the analysis and evidence is there to back them up. It is up to the economists to provide the ammunition.
扭转美国出现的这种集中化程度提高，需要投入可观的政治资本，官僚体系也需要投入大量精力。如果有相关分析和证据作为依据，当局将更有可能采取行动。提供这些弹药是经济学家们的责任。
The writer is professor of economics at the University of Manchester
本文作者是曼彻斯特大学(University of Manchester)经济学教授
