Category Archives: maghic

Professor Miguel Leon-Ledesma

Miguel appointed Fellow of CEPR

Congratulations to Professor Miguel León-Ledesma on his appointment as Fellow of the Centre for Economic Policy Research (CEPR). The prestigious CEPR is a research network of economists established in 1983 to enhance economic policy making in Europe. Based in London, CEPR’s network of Research Fellows and Affiliates includes over 1,000 of the top economists in the world conducting research on issues affecting the European economy. Miguel has been appointed Fellow of the Macroeconomics and Growth programme area.

Dr Katsuyuki Shibayama

A Simple Model of Growth Slowdown

by Dr Katsuyuki Shibayama, University of Kent. Discussion paper KDPE 1813, October 2018.

Non-technical summary:

After the Great Recession around 2007-8, the U.K. has experienced the slowdown of the labour productivity; known as ’productivity puzzle’. Although it is widely recognized as the stagnation of the labour productivity, not surprisingly, it coincides with the flattening of the total factor productivity (TFP). Japan also has experienced a similar but much longer and deeper phenomenon after the bubble burst at the beginning of 1990s. Interestingly, both countries have experienced the growth slowdown after some financial turmoil. This paper aims to explain these growth slowdowns quantitatively in a reasonably realistic economic growth model.

A growth slowdown is a long-lasting, significant decline of growth rate. It is not specific to high-income countries. The economic model developed in this paper also encompasses the “middle income trap”; typical examples include Latin American countries. The standard economic growth theory tells us that low-income countries should grow faster because they tend to accumulate production capital at a faster rate (Solow effect). Actually, many countries has successfully escaped from low income levels, but, out of 101 middle income countries in 1960, only 13 of them is classified as high income countries in 2008; see Larson, Loayza and Woolcock (2016, World Bank).

Extending Romer’s (1990) seminal paper, our model has an additional state variable, which we call the R&D environment, to capture social culture (scientists ’attitudes toward business, etc.), legal system (including patent laws and property rights), R&D infrastructure (such as innovators’ networks and education systems), and so on. We can regard the R&D environment as an intangible social capital, which has the following two properties; (a) society accumulates the R&D environment as an (intangible) asset by conducting R&D; and (b) the R&D activities are more productive when the R&D environment takes a higher value. For (a), an important assumption is such an accumulation of social asset is a positive externality of the R&D activities; i.e., the researchers do not intend to improve the R&D environment, when they engage in R&D. For (b), we want to capture, for example, higher education institutions are better prepared for the commercialization of academic findings when business innovations and inventions are more active.

In our model, there are two stable balanced growth paths (BGPs, long-run equilibria); one with positive R&D activities and the other without them. This is intuitively because of vicious and virtuous cycles. Around the BGP with no R&D, there is a vicious cycle; once R&D becomes inactive, it deteriorates the R&D environment, which itself discourages the R&D activities. Similarly, there is a virtuous cycle in the good BGP.

If there are no shocks (or only small shocks) in the model, then the fate of an economy depends on its initial condition. In our model, depending on the initial state, its final destiny – good BGP or bad BGP – is predetermined. Note importantly that in our model, even an economy moves toward the bad BGP, still it grows at a faster rate in early periods through the capital accumulation (Solow effect); it fails to switch from the capital accumulation as a growth engine to the R&D driven growth. We argue that countries that successfully transited from the middle-income level have had a R&D environment good enough to attain this transition; such as Japan and West Germany after the WWII. This is the explanation of the middle-income trap in our model.

If there are some shocks in the model, even if they are temporary, still they can have long-run effects. We assume that after a successful innovation, innovators can set up a firm, meaning that the firm value is the reward to innovations. Like Comin and Gertler (2003, AER), because the firm value is the present value of the current and future profits, R&D is more active in booms. Unlike Comin and Gertler’s ’medium cycle’ effects, however, business cycle fluctuations can have very persistent effects in our model; this is because a shock may push out an economy from one BGP to the other. For example, if an economy experiences a bad external shock, output, firm profit and firm value decline, which in turn discourages innovations. If such a bad shock is large enough and lasts long enough, the dormant R&D activities during the recession may deteriorate significantly, which hampers R&D even after the end of the negative external shock. In our model, this is the mechanism behind the growth slowdown in Japan and the U.K.

There are several policy implications. First, to help escape from the middle-income trap and the long-lasting growth slowdown, we need a ’big push’. For example, a large scale ODA as a positive external shock may be required. Second, however, the type of ODA matters. In our model, improving production efficiency and increasing final goods demand do not help escape from the low BGP, because there are two effects that offset each other. On the one hand, these shocks increase the firm profit and firm value, which stimulates the R&D activities. However, on the other hand, the production sector and the R&D sector compete each other in the factor market (labour market in our model). Hence, in our model, if the production efficiency improves, the production sector absorbs more labour, squeezing out the R&D sector from the labour market. There is anecdotal evidence of type of phenomenon; e.g., Wall Street and City have taken many scientists from universities and other research institutes such as NASA. In addition, this story is in parallel with the leading exposition about the natural resource curse; if the extraction of natural resources are very profitable, the natural resource sectors absorb too much production factors such as labour, squeezing out high productivity growth sectors such as manufacturing. Hence, if they only improves production efficiency, building bridges, roads and power plants, for example, has little effect in total. Third, our numerical experiments suggest that the financial sector efficiency has a strong effect. If the financial market is malfunctioning, the firm value may be discounted unduly. In our model, because the firm value is the reward to successful R&D, such a mispricing of the firm value discourages the R&D efforts. This is reminiscent of the fact that the U.K. and Japan have experienced the growth slowdown after the financial market turmoil.

In conclusion, this paper asserts that a sort of intangible social assets such as culture, legal system, etc. are important for R&D. Our model has multiple BGPs. Even though an economy has experienced a rapid growth via capital accumulation (Solow effect), it may fail to switch to the R&D driven growth (middle-income trap). In addition, even though a country successfully achieved a high-income level, it could slip down from the good BGP, particularly if it suffers from deep and long financial turmoil (like Japan and the U.K.). To regain the sustainable R&D environment, the model suggests the following policy prescriptions; (i) policy measures that directly affect the R&D productivity such as the subsidy to higher education and R&D tax credit and (ii) policies to improve the efficiency in the financial market.

You can download the complete paper here.

Measured Productivity with Endogenous Markups and Economic Profits

by Dr Anthony Savagar, University of Kent. Discussion paper KDPE 1812, October 2018.

Non-technical summary:

A standard way to measure productivity is to take output growth and subtract input growth. Typically input growth is growth in capital and growth in labor weighted by their share in production. Whatever remains after subtracting is known as total factor productivity (TFP).

Under specific circumstances, this productivity measure also reflects underlying technology growth. This is important for economists because they struggle to measure underlying technology at an aggregate level, but it is a key variable to understand the behaviour of the economy.

However when we diverge from some basic assumptions, such as perfect competition, the TFP measure no longer reflects underlying technology. Therefore using our TFP measure to represent technology could lead to incorrect conclusions.

In this paper I show that when we recognize the slow adjustment of firms to arbitrage profits and the effect that slowly entering firms have on competition, the relationship between our measure of TFP and technology becomes much more complex. In fact, when we observe changing TFP, it will compose changing technology, changing profits and changing markups. This decomposition allows us to understand how we can get a true measure of underlying technology from our calculated TFP measure. It emphasizes that the composition of profits and markups vary in importance as firm entry takes place.

You can download the complete paper here.

Jan-Philipp Dueber

Endogenous Time-Varying Volatility and Emerging Market Business Cycles

by Jan-Philipp Dueber, University of Kent. Discussion paper KDPE 1811, August 2018.

Non-technical summary:

Time-varying volatility plays a crucial role in understanding business cycles in emerging market economies. There is now plentiful empirical evidence that volatility as measured by the standard deviation in macroeconomic data is time-varying and strongly countercyclical. Volatility increases during an economic recession and becomes lower during an economic boom.

In addition, we observe that standard open-economy macroeconomic models widely used for business cycle analysis fail to address the specific characteristics of many emerging market economies. In emerging market economies the net export to output ratio is typically negatively correlated with output i.e. it is countercyclical. However, standard models predict a near perfect positive correlation between the two. Besides that, emerging market economies show a higher fluctuation in consumption data than in data on output. Standard models, however, predict a higher fluctuation in output than consumption. These models are therefore overemphasizing the role of consumption smoothing.

This work is motivated by the above empirical observations. We augment a standard small-open economy model and introduce time-varying volatility to the interest rate and total factor productivity. In our model the interest rate and total factor productivity automatically turn more volatile when the economy becomes more indebted or when output declines in response to a negative total factor productivity shock. Once we introduce time-varying volatility into a standard open-economy model, the model becomes able to significantly better match emerging market economy data. After the introduction of a time-varying interest rate and total factor productivity we are able to present a model where net exports are strongly negatively correlated with output and consumption shows a higher variation than output as observed in the data. By choosing different parameter values for the time-varying volatility the model is able to characterize both, emerging market and developed economies, or an economy that is in transition to a developed economy.

Although we are not the first to address the problems of macroeconomic models for emerging market economies, our approach is especially simple and does not rely on shocks to the permanent component of total factor productivity or to shocks in the level of the interest rate. Compared to other research in this area our approach only requires one source of external variation, the widely used shock to total factor productivity. From a policy point of view our model can be especially useful for economists and policy makers in emerging market economies as our model now better fits the economic cycle in those countries.

You can download the complete paper here.

Grant success for Anthony!

Congratulations to Dr Anthony Savagar, Lecturer in Macroeconomics, on winning an ESRC Research Award for £200,000 for his project ‘Firm Dynamics, Market Power and Productivity Puzzles’.

The UK economy faces a productivity puzzle: persistently low levels of output per worker since the 2007 Great Recession, which are largely unexplained. The aim of the project ‘Firm Dynamics, Market Power and Productivity Puzzles’ is to analyse UK business microdata to understand whether changes in firms’ market power have influenced UK productivity since 2007. It will also question whether entry and exit of firms into industries disrupted market power to affect productivity. The objective is to improve understanding of the UK productivity puzzle and to better understand policies affecting market power which may widen the current industrial strategy debate.

Anthony is the Principal Investigator with Professor Miguel Leon-Ledesma as the is the Co-Investigator.

Keynes College

Population Aging, Government Policy and the Postwar Japanese Economy

by Keisuke Otsu, Keio University and University of Kent; and Katsuyuki Shibayama, University of Kent. Discussion paper KDPE 1809, July 2018.

Non-technical summary:

The Japanese economy has gone through important transitions during the postwar period such as the gradual slowdown in economic growth and the steady increase in the share of people aged above 65 years old among the adult population. In this paper we construct a parsimonious neoclassical growth model to quantitatively assess the impact of population aging and various government policies on output growth in Japan over the 1975-2015 period.

We consider several interactions between government policies and population aging. First, labor income tax has been rising steadily as the social security burden of the working age population has increased. Next, population aging tends to decrease employment and increase hours worked per worker in exchange; the workweek reduction policy introduced in the late 1980s is crucial to account for the decline in hours worked per worker during this period. Finally, the composition of fiscal spending has shifted from public investment to medical expenditure as the demand for health care services has risen.

Our main findings are that:

i) the increase in the aged-population share can account for most of the decline in employment and reduced output by 8% from its potential level

ii) workweek shortening policy led to a 20% reduction in output from its potential level by reducing hours worked over the 1988-1992 period

iii) labor income tax led to an 11% reduction in output from its potential level by discouraging hours worked

iv) the shift in the composition of government spending may have caused a slowdown in productivity growth and hence a reduction in the potential output level itself

You can download the complete paper here.


Professor Miguel Leon-Ledesma

The Missing Link: Monetary Policy and The Labor Share

by Cristiano Cantore, University of Surrey; Filippo Ferroni, Federal Reserve Bank of Chicago; and Miguel A. León-Ledesma, University of Kent. Discussion paper KDPE 1808, June 2018.

Non-technical summary:

The mechanisms through which monetary policy (MP) affects inflation and real economic activity are central to macroeconomics. During the past few decades, New Keynesian models have constituted the dominant view of that transmission mechanism. In those models, MP affects inflation and real economic activity through the effect of interest rate changes on firms’ mark-ups over marginal costs of production. Changes in mark-ups have a redistributive effect between labour and profits. The essence of that mechanism in its simplest version is as follows: when prices cannot adjust immediately, a monetary policy contraction that reduces demand implies that prices are too high relative to optimal because firms cannot lower prices to adjust to the fall in demand; since prices are above optimal, firms are charging a higher mark-up after the contractionary MP surprise. Since mark-ups rise, the labour share of income falls and the profit share (mark-ups) increases. Thus, we would expect that, after a MP contraction, cyclically, the labour share would fall.

In this paper we provide comprehensive evidence on the effect of MP surprises on the labour share for five developed countries (Australia, Canada, EU, US, and the UK) using state of the art econometric techniques. Contrary to the expected result from the basic New Keynesian model, we find that, systematically, the labour share increases cyclically after a MP contraction. This fact is robust to different countries, measures of the labour share, sample periods, econometric model specifications, shock identification methods, and sectors. The reason why the labour share increases is because real wages fall but labour productivity falls more than real wages. Since the labour share is simply the ratio of the two, it increases after a contractionary MP surprise.

We then ask whether macroeconomic models widely used to analyse the effect of MP on the economy are well equipped to reproduce that response. In more elaborate versions of the New Keynesian model that incorporate different real and nominal rigidities in the economy, the direct relationship between mark-ups and the labour share breaks down. Hence, potentially, these models can generate a response of the labour share in line with our data findings.

We analyse models incorporating a cost channel of MP, fixed costs of production, different production functions, and search and matching frictions in the labour market. The models are analysed numerically allowing for a wide range of behavioural and market structure parameter combinations. Our analysis shows that, even in these more elaborate versions, the models fail to reproduce the increase in the labour share after a MP contraction that we observe in the data.

You can download the complete paper here.

Effects of population ageing

The School’s Dr Katsuyuki Shibayama (Principal Investigator), Professor Miguel León-Ledesma, and Dr Keisuke Otsu (Keio University and Honorary Lecturer at Kent) have received funding from the Murata Foundation in Japan for 2 million Yen for a project entitled: A quantitative analysis of population ageing on economic growth and income inequality.

The project aims at understanding the consequences of population ageing for the joint dynamics of growth and income distribution. Its objective is to construct a model of overlapping generations where families choose the number of children and their level of education. The model will then be used to analyse the effect of different “anti-ageing” policies on growth and income distribution, namely: female employment support, child-care support, and higher education subsidies.

The model is targeted to reproduce the case of the Japanese economy, one of the more rapidly ageing societies, but will also draw implications for other economies expected to go through a similar demographic experience. The project also consolidates the close links between Kent and Keio, who currently have a student exchange agreement.

Money, Macro and Finance PhD Conference

The School of Economics is pleased to be hosting the 5th Money, Macroeconomics and Finance (MMF) PhD Conference on 19-20 April 2018.

The conference will include sessions on macro-labour; networks effects; macro-finance; international macro; macroeconometrics; and firms, chaired by academics from each of the sponsoring institutions.

Full details and the programme can be found on our website at

Sponsored by the Money, Macro and Finance Research Group; the Bank of England; the Macroeconomics, Growth and History Centre (MaGHiC), University of Kent; the Centre for International Macro Studies (CIMS), University of Surrey.

Professor Miguel Leon-Ledesma

International Centre for Pension Management Award

A paper by Professor Miguel León-Ledesma on ‘Population structure and asset values’ has received the 2017 International Centre for Pension Management Award.

The paper, co-authored with Kate Rybczynski, Lori Curtis, Stephen Bonnar (University of Waterloo), Jaideep Oberoi (University of Kent), and Mark Zhou (CMHC), analyses the effect of changes in the age structure of population on the prize of risky and non-risky assets. Its results are important for the management of pension systems, as it helps forecasting future returns in countries where the age structure is rapidly changing towards a larger weight of pension-age population.

The prize, endowed with 10,000 CAD, will be used to fund further research in the area by the team. The paper also received the Best Paper Award 2018 by the International Conference of Actuaries 2018.