Schumpeterian Growth Model Research Articles

A Schumpeterian exploration of Gini and top/bottom income shares

Abstract Data show that an increase in the Gini coefficient is associated with a falling bottom $p_{B}$ % income share and an increasing top $p_{T}$ % income share where, for example $p_{B}$ = 40 and $p_{T}$ = 1. This relationship, which we call the $X$ inequality relationship, is pervasive in the sense that it is observed in many countries, including the US, the UK, France and others. The purpose of this paper is (i) to construct a Schumpeterian growth model to explain the relationship, and (ii) to identify/quantify factors behind it via calibration of the US economy. Our model gives rise to a double-Pareto distribution of income as a result of entrant and incumbent innovations. Its advantage is that it allows us to develop iso-Gini loci and iso-income share schedules in a tractable way. Using a double-Pareto distribution as an approximation of an underlying income distribution, calibration analysis reveals that a declining business dynamism and fiscal policy changes in the past decades played a significant role in generating the $X$ inequality relationship in the US.

Endogenous innovation scale and patent policy in a monetary schumpeterian growth model

Abstract This paper develops a monetary R&D-driven endogenous growth model featuring endogenous innovation scales and the price-marginal cost markup. To endogenize the step size of quality improvement, we propose a tradeoff mechanism between the risk of innovation failure and the benefit of innovation success in R&D firms. Several findings emerge from the analysis. First, a rise in the nominal interest rate decreases economic growth; however, its relationship with social welfare is ambiguous. Second, either strengthening patent protection or raising the professional knowledge of R&D firms leads to an ambiguous effect on economic growth. Third, the Friedman rule of a zero nominal interest rate fails to be optimal in view of the social welfare maximum. Finally, our numerical analysis indicates that the extent of patent protection and the level of an R&D firm’s professional knowledge play a crucial role in determining the optimal interest rate.

Inequality, openness, and growth through creative destruction

We examine how inequality and openness interact in shaping the long-run growth prospects of developing countries. To this end, we develop a Schumpeterian growth model with heterogeneous households and non-homothetic preferences for quality. We show that inequality affects growth very differently in an open economy as opposed to a closed economy: If the economy is close to the technological frontier, the positive demand effect of inequality on growth found in closed-economy models may be amplified by international competition. In countries with a larger distance to the technology frontier, however, rich households satisfy their demand for high quality via importing, and the effect of inequality on growth is smaller than in a closed economy and may even be negative. In such case trade gives rise to the endogenous emergence of a ‘dual economy’ where some domestic sectors are highly innovative while others are lagging behind.

Declining research productivity and income inequality: A centenary perspective

Research productivity has been sharply declining since 1920. This decline has significant implications for inequality. Using an open-economy Schumpeterian growth model, we show that domestic research productivity influences income inequality through two opposing forces: a positive effect from increased asset returns and a negative effect from the erosion of innovation rents through creative destruction. In contrast, foreign research productivity affects inequality solely through the asset returns channel. By constructing a long historical data series for 21 OECD countries, we find that the asset returns channel has been the dominant driver of inequality over the past century. The reduction in both domestic and foreign R&D productivity accounts for 25% to 35% of the observed downward trend in income inequality over this period.

Inflation and income inequality in an open-economy growth model with liquidity constraints on R&D

This study presents a framework to understand the relationship between inflation and income inequality in an open-economy Schumpeterian growth model with heterogeneous households, firm-level innovation, and cash-in-advance constraints on R&D investment. We show that the global real interest rate channel can play a key role in defining this relationship. In smaller economies that have negligible impacts on the global interest rate, income inequality is likely to exacerbate as inflation rates rise. In contrast, for larger economies that can significantly affect the global interest rate, inflation and income inequality may demonstrate a U-shaped relationship. These theoretical predictions are supported by the quantitative analysis in a model calibrated to the economies of the US and the eurozone, as well as empirical estimates using cross-country data.

Patent protection, externalities, and income inequality

AbstractThis paper develops a Schumpeterian growth model with considering consumption and leisure externalities. The main purpose of this study is to investigate the effect of patent protection policy on growth and inequality, as well as the interaction between policy effect and externalities. According to the log form utility function specification, this means that the elasticity of intertemporal substitution is unity. The following are the key findings of this paper. Patent protection policy encourages innovation and increases employment in the R&D industry, which enhances economic growth while increasing income inequality. In regard to externalities, an increase in the degree of consumption (leisure) externalities results in a higher (lower) growth rate and more (smaller) income inequality. When consumption (leisure) externality is greater intensity, the growth effect of patent protection policy becomes stronger (weaker), while its influence on expanding income inequality lessens (enhances). Finally, both the Pareto optimal patent protection policy and the optimal patent policy under the maximization of social welfare positively correlate with consumption externalities, but negatively correlate with leisure externalities.

Dynamic effects of tourism shocks on innovation in an open-economy Schumpeterian growth model

International travel restrictions during the COVID-19 pandemic drastically reduced the number of tourists. This study explores the dynamic effects of tourism shocks in an open-economy Schumpeterian model with endogenous market structure. A tourism shock affects the economy via a reallocation effect and an employment effect. A positive tourism shock increases employment, which raises production and innovation in the short run. However, a positive tourism shock also reallocates labor from production to service for tourists, which reduces production and innovation. If leisure preference is weak, the reallocation effect dominates, and the short-run effect of positive tourism shocks on innovation is monotonically negative. If leisure preference is strong, the employment effect dominates initially, and the short-run effect of tourism shocks on innovation becomes inverted-U, which is consistent with the stylized facts that we document using cross-country data. Finally, permanent tourism shocks do not affect the steady-state innovation rate in our scale-invariant model.

R&D and Education Subsidies in a Monetary Schumpeterian Growth Model

R&D and Education Subsidies in a Monetary Schumpeterian Growth Model

Blocking patents, rent protection and economic growth

We develop a Schumpeterian growth model to analyze the interaction between patent policy and firms' internal strategies to capture value from innovations. We consider two dimensions of patent policy: backward protection against imitation and forward protection, also known as blocking patents, against subsequent innovation that builds on a patented technology. Incumbent patent holders endogenously invest resources to protect their monopoly rents by impeding market entry of innovative competitors. We show that patent policy impacts economic growth through its influence on both the ex ante R&D incentives of potential innovators and the post-innovation rent protection incentives of incumbent firms. Most importantly, our analysis formalizes a novel growth-promoting role of forward protection; by guaranteeing previous innovators a share of future innovators' profits, forward protection reduces the incentive to actively obstruct follow-on innovations. We identify conditions under which the selective use of forward protection can stimulate economic growth through this mechanism.

Haste makes waste? Quantity-based subsidies under heterogeneous innovations

With quantity-based innovation targets and subsidy programs launched since the mid-2000s, China has seen a patent surge, accounting for 46% of the world’s total patent applications in 2020; however, the overall patent quality has been declining after 2008. This paper develops a Schumpeterian growth model featuring innovating firms’ quantity–quality trade-off between radical and incremental innovations, and decomposes subsidies’ aggregate impact into quantity and quality channels. We calibrate the model to Chinese firm-level data in the early 2010s. Our quantitative analysis shows that the quality channel effects are negative and dominant, and quantity-based subsidies in that period reduce the TFP growth rate and welfare by 0.19 percentage points and 3.31%, respectively. We evaluate welfare gains under a constrained planner’s problem, and propose skill subsidies which are quality-biased and effectively recover the optimal allocation.

Export-led takeoff in a Schumpeterian economy

This study develops an open-economy Schumpeterian growth model with endogenous takeoff to explore the effects of exports on the transition of an economy from stagnation to innovation-driven growth. We find that a higher export demand raises the level of employment, which causes a larger market size and an earlier takeoff along with a higher transitional growth rate but has no effect on long-run economic growth. These theoretical results are consistent with empirical evidence that we document using cross-country panel data in which the positive effect of exports on economic growth becomes smaller, as countries become more developed, and eventually disappears. We also calibrate the model to data in China and find that its export share increasing from 4.6% in 1978 to 36% in 2006 causes a rapid growth acceleration, but the fall in exports after 2007 causes a growth deceleration that continues until recent times.

Public debt and welfare in a quantitative Schumpeterian growth model with incomplete markets

This paper quantifies the welfare effects of counterfactual public debt policies using an endogenous growth model with incomplete markets. The economy features public debt, Schumpeterian growth, infinitely-lived agents, uninsurable income risk, and discount factor heterogeneity. Two versions of the model are specified, one with households holding equity in the group of innovating firms. The model is calibrated to the U.S. economy to match the degree of wealth inequality, the share of R&D expenditure in GDP, the firms’ exit rate, the average growth rate, and other standard long-run targets. When comparing balanced growth paths, I find large welfare gains in equilibria characterized by governments accumulating public wealth. The result is robust to the mechanism used to generate a highly concentrated wealth (i.e., preference heterogeneity or “superstar” income shocks). Welfare effects decompositions show that level effects and growth effects reinforce each other. The responses of both the intermediate goods and their market conditions are key in explaining the large level effects. The version of the model without equity is computationally easier to solve, allowing to consider transitional dynamics. Taking into account the dynamic adjustment to the new long-run equilibrium, I show that the transitional welfare costs are not large enough to change the sign of the welfare effects stemming from a change in public debt. I find that eliminating public debt would lead to a 0.8% increase in welfare, while moving to a debt/GDP ratio of 100% would entail a welfare loss of 0.5%. A decomposition analysis shows that growth accounts for approximately 50% of the overall welfare effects.

Patent term extensions and commercialization lags in the pharmaceutical industry: A growth-theoretic analysis

Due to the lags in commercialization, the effective life of a patent is generally less than its statutory term. We introduce commercialization lags into the Schumpeterian growth model and explore the effects of patent term extensions on pharmaceutical R&D and social welfare. Our results show that extending patent terms stimulates the consumption of homogeneous goods but generates an ambiguous effect on the consumption of pharmaceuticals. When patent extensions have an inverted-U effect on social welfare, the optimal patent extension increases with the length of commercialization lags but decreases with the input intensity of commercialization lags. Finally, we calibrate the model and find that increasing patent breadth reduces the optimal patent extension.

Connecting to Power: Political Connections, Innovation, and Firm Dynamics

How do political connections affect firm dynamics, innovation, and creative destruction? We extend a Schumpeterian growth model with political connections that help firms ease bureaucratic and regulatory burden. The model highlights how political connections influence an economy's business dynamism and innovation, and generates a number of implications guiding our empirical analysis. We construct a new large‐scale data set for the period 1993–2014, on the universe of firms, workers, and politicians, complemented with corporate financial statements, patent data, and election data, so as to define connected firms as those employing local politicians. We identify a leadership paradox: market leaders are much more likely to be politically connected, but much less likely to innovate. Political connections relate to a higher rate of survival, as well as growth in employment and revenues, but not in productivity—a result that we also confirm using the regression discontinuity design. At the aggregate level, gains from political connections do not offset losses stemming from lower reallocation and growth.

R&D, Industrial Policy and Growth

An issue with estimating the impact of industrial support is that the firms that receive support may be politically connected, introducing omitted variable bias. Applying fixed-effects regressions on Vietnamese panel data containing several proxies for political connectedness to correct this bias, we find that firms that receive industrial support in the form of tax holidays experience more rapid productivity growth, particularly in R&D-intensive industries, and less so among politically connected firms. These findings do not appear to be due to the presence of financing constraints. We then develop a second-generation Schumpeterian growth model with many industries, and show that tax holidays disproportionately raise productivity growth in R&D-intensive industries. These results are significant and important for governments, especially those in transition and developing countries, in better targeting their industrial policy to facilitate higher productivity growth.

Persistence analysis of research intensity in OECD countries since 1870

AbstractThis paper analyses the persistence of research intensity in the OECD over the period 1870–2018. The goal is to test if the conclusion of the study conducted by Ang and Madsen (Ang, J. B., & Madsen, J. B. (2011). Can second‐generation endogenous growth models explain the productivity trends and knowledge production in the Asian miracle economies? The Review of Economics and Statistics 2011, 93(4), 1360–1373), namely that the Schumpeterian growth models predict that research intensity is stationary, is correct. Using fractional integration methods on annual research intensity from 16 OECD countries, we observe that the series are very persistent. The order of integration is observed to be statistically higher than 1 in all the countries except Spain, rejecting thus the hypothesis of stationarity. When the likelihood of non‐linear trends is considered in the analysis, the results are not materially different. An implication of the results is that policies aimed at boosting research activities will have a long‐term impact on research intensity.

Agricultural revolution and industrialization

This study explores how agricultural technology affects the endogenous takeoff of an economy in the Schumpeterian growth model. Due to the subsistence requirement for agricultural consumption, an improvement in agricultural technology reallocates labor from agriculture to the industrial sector. Therefore, agricultural improvement expands firm size in the industrial sector, which determines innovation and triggers an endogenous transition from stagnation to growth. Calibrating the model to data, we find that without the reallocation of labor from agriculture to the industrial sector in the early 19th century, the takeoff of the US economy would have been delayed by about four decades.

Product innovation, diffusion and endogenous growth

We develop a model of Schumpeterian growth featuring a stochastic diffusion process where the rate of commercial success of product innovations is endogenously determined by advertising intensity. We consider both informative advertising, which young technological leaders use to increase the probability of diffusion, and defensive advertising, which incumbents use to prevent the diffusion of competing products. Economic growth depends positively on the arrival rate of product innovations and the diffusion rate of innovations into the mainstream market. We show that R&D subsidies shift relative investment incentives towards innovation and away from diffusion. This creates an inverted U-shaped relationship between R&D subsidies and both economic growth and welfare as innovations arrive more frequently, but fewer commercialize successfully. We find that advertising subsidies increase diffusion, growth, and welfare when advertising is purely informative. In the presence of defensive advertising, advertising subsidies lead to socially wasteful increases in resources devoted to advertising without large increases in diffusion, reducing growth and welfare.

Should the government subsidize innovation or automation?

AbstractThis study introduces automation into a Schumpeterian growth model to explore the effects of R&D and automation subsidies. R&D subsidy increases innovation and growth but decreases the share of automated industries and the degree of capital intensity in the aggregate production function. Automation subsidy has the opposite effects on these macroeconomic variables. Calibrating the model to US data, we find that raising R&D subsidy increases the welfare of high-skill workers but decreases the welfare of low-skill workers and capital owners, whereas increasing automation subsidy increases the welfare of high-skill workers and capital owners but decreases the welfare of low-skill workers. Therefore, whether the government should subsidize innovation or automation depends on how it evaluates the welfare gains and losses of different agents in the economy.

Semi-endogenous Versus Schumpeterian Growth Models: A Critical Review of the Literature and New Evidence

Abstract Several studies have tested semi-endogenous versus Schumpeterian growth models using different methodological approaches. This paper critically reviews these studies including their approaches and provides new evidence on this issue, by analyzing both time-series data from the United States and panel data from 19 OECD countries over the period 1980–2014. The review finds much support for Schumpeterian growth theory, but shows that all studies reviewed have several limitations. These limitations include conceptual problems associated with the use of the number/stock of patents as a measure of the flow/stock of knowledge, the possibility of spurious regressions due to non-stationary data, potential mismeasurement of R&D inputs due to possible interpolation and deflation errors, misspecification problems that can arise in difference models when variables are cointegrated, and potential spurious rejections of the unit root hypothesis for R&D intensity when the lag length in unit root tests is too small. The present study avoids these limitations and finds strong evidence in favor of semi-endogenous growth.