Schumpeterian Growth Model Research Articles

Intellectual Property Law and Public Sponsorship of R & D in a Schumpeterian Growth Model with Fundamental and Applied R & D

Dans le cadre d’un modèle de croissance Schumpétérien, nous étudions comment le droit de la propriété intellectuelle et le financement public des activités de recherche et de développement peuvent permettre de donner des incitations adaptées simultanément à la recherche fondamentale et à la recherche appliquée. Nous développons un modèle distinguant ces deux types d’activités de recherche en fusionnant les modèles séminaux de Romer [1990] et de Aghion et Howitt [1992] ; ainsi, l’accumulation de connaissance découle conjointement d’une série d’inventions (accumulation horizontale de connaissance résultant de l’activité de recherche fondamentale) et d’une succession d’innovations qui s’appuient sur chacune de ces inventions (accumulation verticale de connaissance résultant de l’activité de recherche appliquée). Dès lors, nous étudions une économie décentralisée dans laquelle les investissements dans la recherche fondamentale ne sont pas entravés par le mécanisme de destruction créatrice grâce à un droit de la propriété intellectuelle qui induit une répartition des profits entre tout inventeur et les innovateurs qui lui succèdent. Nous montrons que la mise en place d’incitations optimales à la recherche fondamentale requiert non seulement un droit de la propriété intellectuelle assurant un transfert suffisant de profits des innovateurs vers les inventeurs, mais également un soutien financier public de la recherche, sous forme de subventions destinées à la recherche fondamentale mais aussi à la recherche appliquée.

ASSET PRICE BUBBLES AND TECHNOLOGICAL INNOVATION

We introduce borrowing constraints into a two‐sector Schumpeterian growth model and examine the impact of asset price bubbles on innovation. In this environment, rational bubbles arise when the intermediate good producing R&D sector is faced with adverse productivity shocks. Importantly, these bubbles help alleviate credit constraints and facilitate innovation in the stagnant economy. On the policy front, we make a case for debt financed credit to the R&D sector. Further, we establish that a constant credit growth rule (akin to the Friedman rule) outperforms the often prescribed counter‐cyclical “lean against the wind” credit policy. (JEL E32, E44, O40)

Inflation and innovation with a cash-in-advance constraint on human capital accumulation

This note explores a novel channel – a cash-in-advance (CIA) constraint on endogenous human capital investment – through which monetary policy impacts growth and welfare in a scale-invariant Schumpeterian growth model. We find the following. An increase in the nominal interest rate leads to a decrease in human capital investment, which in turn reduces long-run growth and welfare. Calibration shows that long-run growth increases 0.61% by reducing the nominal interest rate from 9.9% (the sample mean of the U.S.) to 0%. The corresponding welfare gain is equivalent to a permanent increase in consumption of 15.98%. The growth and welfare effects depend on the strength of the CIA constraint on human capital investment. Our study has strong policy implications for developing countries where out-of-pocket money may be important for schooling.

Inflation and health in a Schumpeterian growth model: Theory and evidence

Researchers have found many benefits of good health. However, health investment may be subject to borrowing constraints. In this study, we incorporate endogenous health investment in a scale-invariant Schumpeterian growth model. We find the following. When the cash-in-advance (CIA) constraint does not apply to medical expenditures, long-run growth does not depend on the nominal interest rate. In contrast, when the CIA constraint does apply to medical expenditures, an increase in the nominal interest rate leads to a decrease in both R&D and health investment, which in turn reduce the long-run growth rates of technology and output. Nevertheless, welfare is always a decreasing function of the nominal interest rate, and the welfare loss is greater under the CIA constraint on medical expenditures. As an empirical test, we build panel data for 61 countries during the years 1995–2014. We find a significant, negative effect of inflation on out-of-pocket health expenditure (% of total expenditure on health) of the World Development Indicators of the World Bank, which provides support for our theory. The policy implication is that government financing of health care for the poor can offset this effect.

R&D policy and competition in a Schumpeterian growth model with heterogeneous firms

This paper presents a second-generation Schumpeterian growth model to investigate the existence of possible links between firms’ size, competition stiffness and the effectiveness of R&D policy. In the model, the step size of innovation is randomly drawn from a Pareto distribution, and firms are heterogeneous in terms of market power. The paper finds that the optimal R&D policy is to subsidize R&D and not to tax it, and that more intense competition enlarges the gap between free-market R&D investment and the optimal outcome. However, the paper also finds that the short-run impact on welfare of R&D policy is always negative, and that the recovery time of the welfare loss as a result of the subsidy is negatively related to firms’ market power.

A SCHUMPETERIAN GROWTH MODEL WITH FINANCIAL INTERMEDIARIES

This study introduces financial intermediaries into the Schumpeterian growth model developed by Aghion et al. (2005, Quarterly Journal of Economics, Vol. 120, pp. 173–222). They collect deposits from households, provide funds for entrepreneurial projects, and monitor the entrepreneurs. I consider an economy with moral hazard problems: entrepreneurs can hide the result of a successful innovation and thereby avoid repaying financial intermediaries if the latter do not monitor entrepreneurial performance. I analyze the effects of financial intermediaries' activities on technological progress and economic growth in such an economy. I show that financial intermediaries need to monitor entrepreneurs in an economy where the legal protection of creditors is not strong enough. Such monitoring can resolve the moral hazard problem; however, it does not always promote technological innovation, because it could increase the cost of entrepreneurial innovation and thus reduce the amount invested for innovation. I also examine how monitoring by financial intermediaries affects the welfare of individuals through the stringency of financial markets.

Inflation and fertility in a Schumpeterian growth model: Theory and evidence

This study explores a novel channel for monetary policy to impact growth and welfare—through fertility choice. In a scale-invariant Schumpeterian growth model with endogenous fertility and a cash-in-advance constraint on consumption, we find a positive effect of an increase in the nominal interest rate on fertility. The increase in fertility decreases labor supplied to production and R&D, which in turn decreases long-run growth. Calibration shows that long-run growth increases 0.12% by reducing the nominal interest rate from 9.6% to 0%, and the welfare gain is equivalent to a permanent increase in consumption of 3.14%. As an empirical test, we build panel data for 12 advanced countries during 2000–2014. We use the degree of central bank independence and money growth as the instruments for inflation. We find that the effect of inflation on population growth is positive and significant in instrumental variables estimation. Our results remain robust to using birth rate or fertility rate as the dependent variable. An increase in annual inflation of 1 percentage point would bring an increase of 0.06 percentage point in the annual growth of the total population. Our empirical findings provide support for our theory.

A PATENTABILITY REQUIREMENT AND INDUSTRY-TARGETED R&D

I introduce a minimum innovation size required for patents into a Schumpeterian growth model. We show that to satisfy the patentability requirement for minimum innovation size, each research and development (R&D) firm targets only industries in which the incumbent's technology is of sufficient obsolescence. This is because the technological gap between innovator and incumbent is greater in industries using older technologies. Although the increase in minimum innovation size reduces the number of industries targeted for R&D, it also increases the amount of R&D investment directed at those targeted industries. Consequently, introducing a minimum innovation size has a nonmonotonic (or negative) effect on the aggregate flow of innovations. Further, by deriving the endogenous long-run distribution of innovation size, we show that an increase in minimum innovation size reduces the mean innovation size. This implies that even if the patent office only grants patents for superior innovations, it causes innovators to produce generally inferior-quality innovations.

Effects of patents versus R&D subsidies on income inequality

This study explores the effects of patent protection and R&D subsidies on innovation and income inequality using a Schumpeterian growth model with heterogeneous households. We find that although strengthening patent protection and raising R&D subsidies have the same macroeconomic effects of stimulating innovation and economic growth, they have drastically different microeconomic implications on income inequality. Specifically, strengthening patent protection increases income inequality whereas raising R&D subsidies decreases (increases) it if the quality step size is sufficiently small (large). An empirically realistic quality step size is smaller than the threshold, implying a negative effect of R&D subsidies on income inequality. We also calibrate the model to provide a quantitative analysis and find that strengthening patent protection causes a moderate increase in income inequality and a negligible increase in consumption inequality whereas raising R&D subsidies causes a relatively large decrease in both income inequality and consumption inequality.

Wealth Inequality in the Long Run: A Schumpeterian Growth Perspective

This paper extends Piketty’s analysis of the wealth-income ratio used as a proxy for wealth inequality, to allow for innovation. Drawing on a Schumpeterian (R&D-based) growth model that incorporates both tangible and intangible capital and using historical data for 21 OECD countries, we find the wealth-income ratio to be significantly and positively related to R&D intensity and the fixed capital investment ratio, but negatively related to income growth. Accounting for the innovation-induced counteracting growth-effect on the wealth-income ratio, we show that the net effect of R&D on wealth inequality is positive.

Global Economic Growth and Agricultural Land Conversion under Uncertain Productivity Improvements in Agriculture

AbstractWe study how stochasticity in the evolution of agricultural productivity interacts with economic and population growth at the global level. We use a two‐sector Schumpeterian model of growth, in which a manufacturing sector produces the traditional consumption good and an agricultural sector produces food to sustain contemporaneous population. Agriculture demands land as an input, itself treated as a scarce form of capital. In our model both population and sectoral technological progress are endogenously determined, and key technological parameters of the model are structurally estimated using 1960‐2010 data on world GDP, population, cropland and technological progress. Introducing random shocks to the evolution of total factor productivity in agriculture, we show that uncertainty optimally requires more land to be converted into agricultural use as a hedge against production shortages, and that it significantly affects both optimal consumption and population trajectories.

HUMAN CAPITAL AND INNOVATION IN A MONETARY SCHUMPETERIAN GROWTH MODEL

This study explores the growth and welfare effects of monetary policy in a scale-invariant Schumpeterian growth model with endogenous human capital accumulation. We model money demand via a cash-in-advance (CIA) constraint on research and development (R&D) investment. Our results can be summarized as follows. We find that an increase in the nominal interest rate leads to a decrease in R&D and human capital investment, which, in turn, reduces the long-run growth rates of technology and output. This result stands in stark contrast to the case of exogenous human capital accumulation in which the long-run growth rates of technology and output are independent of the nominal interest rate. Simulating the transitional dynamics, we find that the additional long-run growth effect under endogenous human capital accumulation amplifies the welfare effect of monetary policy. Decreasing the nominal interest rate from 10% to 0% leads to a welfare gain that is equivalent to a permanent increase in consumption of 2.82% (2.38%) under endogenous (exogenous) human capital accumulation.

Inflation and economic growth in a Schumpeterian model with endogenous entry of heterogeneous firms

This study develops a Schumpeterian growth model with endogenous entry of heterogeneous firms to analyze the effects of monetary policy on economic growth via a cash-in-advance constraint on R&D investment. Our results can be summarized as follows. In the special case of a zero entry cost, an increase in the nominal interest rate decreases R&D, the arrival rate of innovations and economic growth as in previous studies. However, in the general case of a positive entry cost, an increase in the nominal interest rate affects the distribution of innovations that are implemented and would have an inverted-U effect on economic growth if the entry cost is sufficiently large. We also calibrate the model to aggregate data of the US economy and find that the growth-maximizing inflation rate is about 3%, which is consistent with recent empirical estimates. Finally, we also explore the welfare effects of inflation and consider a number of extensions to the benchmark model.

GLOBAL POPULATION GROWTH, TECHNOLOGY, AND MALTHUSIAN CONSTRAINTS: A QUANTITATIVE GROWTH THEORETIC PERSPECTIVE

We structurally estimate a two‐sector Schumpeterian growth model with endogenous population and finite land reserves to study the long‐run evolution of global population, technological progress, and the demand for food. The estimated model closely replicates trajectories for world population, GDP, sectoral productivity growth, and crop land area from 1960 to 2010. Projections from 2010 onward show a slowdown of technological progress, and, because it is a key determinant of fertility costs, significant population growth. By 2100, global population reaches 12.4 billion and agricultural production doubles, but the land constraint does not bind because of capital investment and technological progress.

TECHNOLOGY ADOPTION DURING THE PROCESS OF DEVELOPMENT: IMPLICATIONS FOR LONG-RUN PROSPECTS

Most papers studying the impacts of technology adoption on income trajectories assume that firms adopt frontier technologies when available. If these technologies are skill intensive, less-developed economies may fail in successfully implementing them and may become trapped in a low-growth equilibrium. Within a Schumpeterian growth model, we show that differences in adoption barriers and incentives to the accumulation of skills produce differences in the technology level that is optimal to adopt. If the economy is not overly distorted, copying nonfrontier technologies helps compensating for the scarcity of skills and increases the likelihood of copying frontier technologies in the long run. If distortions are significant, it may be optimal to copy less-advanced technologies even in the long run. If adoption is not a skill-intensive activity, then copying frontier technologies is always optimal; all economies achieve a high-growth equilibrium and only income differences persist in the long run.

Local growth and access to credit: Theory and evidence

We theoretically and empirically investigate the effects of access to credit on local growth using a Schumpeterian growth model and assuming monopolistic competition between differentiated products of the banking system. We show that access to credit exerts a positive effect on local economic growth. To validate the theoretical prediction we use data on firms and bank branches from 18 emerging European economies.

On the optimality of IPR protection with blocking patents

This paper develops a Schumpeterian growth model with overlapping intellectual property rights to analyze the effects of patent protection that features two policy instruments: patent breadth and the profit-division rule between sequential innovators. The former determines the markup and profits of firms, whereas the latter determines the degree to which a patent blocks the subsequent invention. Elastic labor supply and subsidies for intermediate goods and research are also considered. The main results are as follows. First, patents and subsidies are substitutable in eliminating the distortions of this model. Second, given the limited use of subsidies in practice, we study optimal patent protection with exogenous subsidies and derive the coordination of patent instruments attaining the social optimum. Third, optimizing only the profit-division rule retains the first-best R&D level and growth rate, but optimizing only patent breadth could lead to under- or over-investment in R&D; either of these cases is less welfare-enhancing than optimizing their mix. Finally, the model is calibrated to quantify the welfare gains from the decentralized equilibrium to the outcomes with the optimal patent instrument(s), and these welfare improvements can be substantially large. Hence, this study sheds some light on the optimal design and welfare implications of a patent system that is multidimensional and blocks future innovations.

Trade and firm heterogeneity in a Schumpeterian model of growth

The present paper explores the effect of trade liberalization on the level of productivity as well as the rate of productivity growth in an R&D-based model with heterogeneous firms. We introduce new and plausible features that are absent in existing studies. First, technical progress takes the form of continual quality improvement of products over time. Second, firm entry and exit are endogenously determined due to creative destruction of products. In this framework, we demonstrate that a lower transport cost or export sunk cost unambiguously reallocates resources to R&D and top-quality product industries from low-quality good industries. This means that trade liberalization increases the rate of technical progress as well as the level of manufacturing productivity. These results are found to be robust in an extended model with population growth without scale effects.

Knowledge exhaustibility and Schumpeterian growth

This paper accommodates the new understanding of the limited exhaustibility of knowledge into the Schumpeterian frame of the creative response to articulate a comprehensive model of Schumpeterian growth. The limited exhaustibility of knowledge and its transient appropriability favor the accumulation of a stock of quasi-public knowledge. The increasing stock of quasi-public knowledge together with appropriate knowledge governance conditions account for the secular decline of knowledge costs and the increase of diachronic and pecuniary knowledge externalities. Because of its limited exhaustibility and the consequent accumulability, knowledge is an endogenous endowment that accounts for growth. Unexpected out-of-equilibrium conditions in product and factor markets stir the response of firms. The availability of knowledge externalities accounts for the rate of innovation as they help making the reaction creative so as to enable the introduction of innovations. The search for technological congruence and the secular decline of the cost of technological knowledge accounts for its knowledge intensive direction as it induces the introduction of biased technological changes that augment the output elasticity of knowledge as an input. The limited exhaustibility of knowledge accounts for the secular trend towards the knowledge economy.

Should the government protect its basic research?

Basic research is mainly performed publicly. Yet in the US public research findings were not patentable until 1980, and in other countries are not yet patentable. Patentability renders public research more directed, with less potential waste, but it also restricts private applied research. This paper shows, by means of a multi-stage Schumpeterian growth model, that in the long run the first effect is bound to dominate.