Fiscal Policy and Growth

虽然许多央行都有明确的宏观经济目标，但财政当局显然没有解决任何问题。除了确保偿付能力和提供一些自动稳定器（Leeper，2016），几乎没有证据表明政府政策的设计是以增长为主要目标的。这个项目由ESRC资助，以财政政策和增长为核心。目前，新一轮研究关注的是，当货币政策陷入严重的边际收益递减时，政府在刺激经济增长方面的作用。具体而言，其目标是更好地了解在长期停滞时期，财政政策在短期和长期内对增长的影响程度。长期停滞是指低真实的利率和长期低增长的时代，没有复苏的力量。当自然真实的利率（在充分就业的情况下平衡储蓄供给和投资需求的利率）足够低，以至于无法通过传统的货币政策来实现时，就会发生这种情况。当一组力量持续推高边际储蓄倾向（MPS）或推低边际消费倾向（MPC）时，可能会发生这种情况。假设，有各种机制可以影响这些边际倾向，从而影响自然利率。在国内，如果你同意凯恩斯的观点，那么贫富差距的扩大会让更多的钱落入那些更有可能储蓄的人手中。人口老龄化会创造一种保守消费习惯的文化。技术进步带来的更便宜的资本意味着企业的货币投资减少。从全国范围来看，更多的国际金融风险增加了全球的不确定性。发达国家由此产生的自我保险（通常以外国政府储备的形式），加上发展中国家持续的贸易顺差，造成了储蓄过剩。此外，更严格的金融监管的副产品是使借贷更加困难，降低了一个国家的支出能力。这并不是影响自然真实的利率的潜在机制的详尽清单。然而，如果我们推测许多经济体目前处于长期停滞期，那么纠正其中一些可能会导致持续的高增长。因此，本研究的初步目的是：（a）判断上述机制是否会导致长期的低增长;（B）判断纠正这些机制的政策是否能够暂时或永久地缓解低增长。目前，我正在研究财政再分配对增长的影响。财政再分配是指减少国家内部收入差距的政策。标准化世界收入不平等数据库提供了1960 - 2017年间196个国家的不平等和再分配的可比数据，我得到了两个关键结果。首先，财政再分配有利于增长。对于目前再分配较少的国家和不平等程度较高的国家，这种影响更大。其次，不平等阻碍了增长。根据类似的凸性论证，当不平等已经很高时，不平等对增长的伤害更大。尽管这项研究的政策含义有限，但结果确实暗示了这样一个事实，即在某些情况下，有针对性的政府政策反应可能在促进增长方面发挥作用。在低增长时期和货币政策无法提供令人满意的推动力时，这可能特别有价值。下一步是问：（一）财政政策是否在增长率较低时更能促进增长？和（ii），这种影响更有可能是永久性的，当增长率低？无论分析哪种类型的政策，这将是我博士研究期间要回答的两个关键问题。

Whilst many central banks have clear macroeconomic objectives, it is not obvious that fiscal authorities solve any. Aside from ensuring solvency and providing some automatic stabilisers (Leeper, 2016), there is little evidence to suggest that government policies are designed with growth as its primary goal.This project, funded by ESRC, has fiscal policy and growth at its core. It comes as a new wave of research looks at the role of government in stimulating growth when monetary policy runs into severe diminishing marginal returns. Specifically, the goal is to gain a better understanding of the extent to which fiscal policies can affect growth, in the short- and long-run, in a period of secular stagnation.Secular stagnation refers to an era of low real interest rates and protracted spells of low growth with no force towards their recovery. It occurs when the natural real interest rate, the rate that balances the supply of savings and demand for investment at full employment, is sufficiently low that it cannot be achieved through conventional monetary policy. This may happen when a set of forces consistently push up the marginal propensity to save (MPS) or push down the marginal propensity to consume (MPC). Hypothetically, there are various mechanisms that could influence these marginal propensities and hence the natural rate. Domestically, if one agrees with Keynes, greater wealth disparities put more money in the hands of those more likely to save it. An ageing population creates a culture of conservative spending habits. Cheaper capital, resulting from technological advancements, means less monetary investment for businesses. On a country-wide scale, more international financial risk increases global uncertainty. The resulting self-insurance in developed countries, often in the form of foreign government reserves, alongside persistent trade surpluses in developing countries, creates a savings glut. Also, stricter financial regulations, which have the by-product of making it more difficult to borrow, reduce a countries' ability to spend. This is not an exhaustive list of potential mechanisms affecting the natural real interest rate. However, if we conjecture that many economies are currently in a period of secular stagnation, remedying some of these may lead to persistently higher growth. The preliminary aims of the research are, therefore, to (a) determine whether any of the mechanisms above can lead to permanently lower growth and (b), determine whether policies that remedy these mechanisms can create either temporary or permanent relief to low growth.Currently, I have spent time looking at the impact of fiscal redistribution on growth. Fiscal redistribution refers to policies that reduce income disparities within countries. Using the Standardised World Income Inequality Database, which provides comparable data on inequality and redistribution for 196 countries between 1960-2017, I obtained two key results. Firstly, fiscal redistribution is pro-growth. This effect is greater for countries who currently redistribute less and also for countries who are more unequal. Secondly, inequality is growth-retarding. Following a similar convexity argument, inequality hurts growth more when inequality is already high.Although the policy implications of this research are limited, the results do allude to the fact that, in certain scenarios, targeted government policy responses may have a role to play in generating growth. This could be particularly valuable during periods of low growth and when monetary policy cannot provide satisfactory impetus. The next step in journey is to ask whether; (i) fiscal policy is more growth enhancing when growth is low? And (ii), is this effect more likely to be permanent when growth is low? Regardless of type of policy analyzed, these will be two key question to answer for the duration of my PhD research.