中国就业研究所

Abstract: Most countries exhibit large and persistent geographical differences in wages, income and unemployment rates. A growing class of "place based" policies attempt to address these differences through public investments and subsidies that target disadvantaged neighborhoods, cities or regions. Place based policies have the potential to profoundly affect the location of economic activity, along with the wages, employment, and industry mix of communities. These programs are widespread in the U.S. and throughout the world, but have only recently been studied closely By economists. We consider the following questions: Who benefits from place based interventions? Do the national benefits outweigh the costs? What sorts of interventions are most likely to be effective? To study these questions, we develop a simple spatial equilibrium model designed to characterize the welfare effects of place based policies on the local and the national economy. Using this model, we critically evaluate the economic rationales for place based policies and assess the latest evidence on their effects. We conclude with some lessons for policy and directions for future research.

摘要：大多数国家在工资、收入和失业率方面存在显著且持久的地域差异。而逐渐增多的“因地制宜”政策试图通过针对不发达社区、城市、区域的公共投资和补贴来解决这些差异。因地制宜政策具有能够深刻影响经济活动区位、工资、就业以及社区产业结构的潜力。这些政策在美国和全世界已经很普遍了，但直到最近才被经济学家仔细研究。我们主要考虑以下问题：谁在因地制宜政策中受益？国家的收益是否超过成本？哪种介入是最可能有效的？为了研究这些问题，我们建立了一个能够表现“因地制宜政策”对地方和国家所产生的福利效应大小的空间均衡模型。运用这一模型，我们精准地估计出了因地制宜政策的经济合理性且测评了它们的影响的最新证据。同时，我们还为未来研究的政策和方向提供了一些经验教训。

Conclusion: As our theoretical discussion makes clear, place based policies involve potentially severe equity-efficiency tradeoffs. Economists have just begun to empirically assess the practical magnitude of these tradeoffs, and how they depend upon program design features and the characteristics of the communities being targeted. Most of what we currently know involves the ability of local subsidies to create local jobs —clearly a useful first step, but ultimately an incomplete assessment of the local and national welfare impacts of interest. Our hope is that future empirical research in this area will be driven By more of a focus on the welfare theoretic issues reviewed in this article.

Though our empirical knowledge is limited, there are a number of policy relevant insights that emerge from our theoretical discussion. First and foremost is that policy makers should be careful to consider the unintended consequences that can arise from worker (and firm) mobility. Subsidizing poor or unproductive places is an imperfect way of transferring resources to poor people. Whether it is more or less imperfect than transfers based on personal or household characteristics is an open question, but a first order consideration of any place based policy should be the mobility response it will generate and the likely consequences of that mobility. As we saw in the idealized model of Section 2, the most efficient demand side subsidy was one that yielded no mobility response at all and simply raised local wages. For this to occur, workers had to be unusually attached to their communities for idiosyncratic reasons—that is, they had to be totally unresponsive to prices.

In reality, households will respond to prices, and policymakers need to factor these responses into their planning process. Mobility responses may lead the local cost of living to change, which in turn can lead landlords, some of whom may not live in the community, to capture some of the benefits associated with a policy. This is more likely when the housing market is already tight or when there are sharp restrictions on building. For this reason, it may be advisable to target areas with depressed housing markets and high vacancy rates that have enough slack to absorb a demand increase without a large increase in the cost of living.

It also seems advisable to design subsidies that are difficult to arbitrage via mobility. For example, the Empowerment Zone program ordered wage credits to firms that were contingent upon the employment of local residents. Because moving to very depressed areas is burden-some, this seems to have induced a limited household mobility response, at least in the short run (Busso, Gregory, and Kline, 2013). It may be possible to design even more stringent eligibility criteria that are easy to enforce and target the desired populations. For example one can imagine a spatially targeted subsidy with, say, a five year residency requirement. Efficient policies would target heavily distressed areas into which outsiders are unlikely to migrate. Yet even when subsidies are designed carefully, they need to be assessed relative to the potential effectiveness of person based alternatives such as the EITC.

For instance, the presence of agglomeration economies does not imply that every state or country should attempt to generate a Silicon Valley equivalent from scratch via spatially targeted subsidies. In the case of manufacturing, the productive advantages of concentration appear to be rival (Kline and Moretti, forthcoming), meaning that little is to be gained from redistributing economic activity from areas with dense manufacturing bases towards less developed areas (or vice-versa). Whether other sectors exhibit equivalent behavior is an important open question. But at this time, economists do not have enough information to reliably suggest strategies that can raise aggregate welfare via agglomeration forces.

Perhaps the most obvious areas where place based policies can raise efficiency is in offsetting clearly distortionary prior policies. For example, the spatial bias in income taxes (Albouy, 2009) and the existence of important labor market rigidities can justify offsetting spatially targeted policies. In an ideal world, effciency would be achieved By directly removing existing distortions. But this is not always feasible, politically, institutionally or technologically. Therefore, second best may, in practice, be very attractive relative to the status quo.

尽管实证知识有限，但仍有许多政治见解从我们的理论探讨中出现。首先就是政策制定者应该慎重考虑从工人（或公司）流动性中产生的意外后果。补贴贫穷或生产力低下地区是向穷人转移资源的不完美方式，至于它是否比基于个人或家庭特征的转移方式更不完美仍然是个未解决的问题，但任何因地制宜政策都应首先考虑它所产生的流动性反应及这一反应可能带来的后果。正如我们在第二部分的理想化模型中所看到的，需求方补贴完全不产生流动性反应并仅仅提高当地工资才是最有效的。要实现这一点，工人不得不因为特殊原因附属于其社区，也就是说，他们不得不对价格完全无反应。

在现实中，家庭会对价格产生反应。政策制定者需要把这些因素加入他们的计划过程中。流动反应也许会导致当地生活成本发生变化，这也会导致地主（也许有人并不住在社区中）去抓住政策带来的收益。当住房市场紧缩或当建筑被严格限制的时候，这种情况将可能变为现实。因此，也许对拥有衰退房地产市场与空房率的目标地区更为明智的是，设计不能通过流动性进行套利的附属地也是很明智的。例如，“授权区域”项目根据对当地居民的雇佣情况向公司收取工资声誉。因为迁移到非常衰退的地区是让人有负担的，至少在在短期内这看起来会诱发一个受限的家庭流动性反应。也许可以建立更严格的合适的标准，能够更容易地强制和针对目标人口。比如，一个人可以想象一个空间上的目标补助金（要求其定居5年）。有效的政策能够瞄准那些移民者不愿居住的衰退地区。但即使安居地被认真地设计，他们也需要评估相关的那些具有其他选项的人的潜在影响。

本土化市场不完美的仲裁能够产生出一个潜在的引人注目的情况地案例。当个人与社会回报产生偏差，当地政府也许可以通过重新调整个人激励（税、津贴、针对当体货物的条款）提高对居民福利。然而，本土化市场不完美的出现不表明空间目标是必需的社会需求。尽管因地制宜政策也许会提高目标社区的福利，他们也可能会因为全国统一标准而减弱福利。在将资源投入项目之前，国家政策制定者应该将当地人享受的福利收益与福利损失的成本相比较。