View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by DSpace at VU Ann Reg Sci (1998) 32:7–37 © Springer-Verlag 1998 Spatial perspectives on new theories of economic growth* Peter Nijkamp1, Jacques Poot 2 1 Department of Spatial Economics, Free University Amsterdam, De Boelelaan 1105, 1081 HV Amsterdam, The Netherlands (Tel.: +31-20-44460 94; Fax: +31-20-44460 04; e-mail: [email protected]) 2 School of Economics and Finance, Victoria University of Wellington, P.O. Box 600, Wellington, New Zealand (Tel.: +64-4-4721000; Fax: +64-4-4955014; e-mail: [email protected]) Abstract. A new wave of interest in long-run economic growth emerged since the late 1980s. This paper uses a simple model to illustrate how tech- nological change can be endogenised in macroeconomic theories of growth and then surveys how – through factor mobility, the diffusion of innova- tions and trade – spatial interdependence in a system of regions can influ- ence technological change and growth. Endogenous technological change generates in our illustrative model long-run steady-state growth in a closed economy. However, it turns out that the dynamic impact of spatial inter- dependence depends on the specification of the model. Spatial conver- gence, a steady state with persisting spatial differences in growth rates and unstable growth are all theoretically possible. Issues relating to the role of aggregate demand and policy also receive attention. There is much scope for further theoretical and empirical work on endogenous growth in a spa- tial-economic context, while a better integration of micro and macro level approaches is also desirable. 1. Introduction The spatial-economic landscape exhibits a panorama of changing hills and valleys of welfare levels. Why growth rates differ between nations, or re- gions, is a fundamental question which has intrigued economists ever since Adam Smith’s (1776) “Inquiry into the nature and causes of the wealth of nations”. Research on the subject, however, has not been at a steady pace during the past two centuries. Instead, there have been several waves of in- * This is a revised version of a paper presented at the international seminar on Endogenous Growth and the Space Economy, 19–20 December 1996, Tinbergen Institute, Amsterdam. This paper was written while Poot was Visiting Professor at the Institute of Policy and Plan- ning Sciences of the University of Tsukuba, Japan. The hospitality of the Institute is gratefully acknowledged. 8 P. Nijkamp, J. Poot terest. Temporal and spatial differences in the standard of living were im- portant issues for classical economists such as Adam Smith, Malthus (1798) and Ricardo (1817). Except for Marx’s (1867) alternative interpreta- tion of the driving forces in long-term capitalist accumulation, further ma- jor theorising did not occur until the 20th century. During the first half of this century, Schumpeter (1934) laid the foundations for recent insights into the role of technological change and entrepreneurial competition in long- run development, while Harrod (1939) and, independently, Domar (1946) studied the growth of a Keynesian economy. In their model, the long run growth path would be likely to exhibit either growing unemployment or ac- celerating inflation. The second half of this century has seen two major waves of interest in the macroeconomics of growth. The first of these commenced with the seminal articles by Solow (1956) and Swan (1956), whose neoclassical growth model provided a more plausible description of the long-term path of the economy than the Harrod-Domar model. Yet the major weakness of the standard neoclassical model, and of the wave of theoretical contribu- tions which built upon it, was that it did not provide an explanation for the actual “engines” of long-run growth in income per worker, although its pre- dictions were consistent with several stylised facts of economic develop- ment. The reason for this deficiency was not that economists were ignorant about the causes of spatial or temporal differences in long-run growth rates but, instead, that causes of productivity improvements such as innovation, economies of scale and learning-by-doing had effects on the economy which violated the assumptions of perfect competition and constant returns to scale. As Krugman (1995) argued, the theoretical tools were not yet available in the 1950s to study such phenomena of increasing returns and imperfect competition within the accepted axiomatic neoclassical frame- work. Consequently, policy makers requiring advice on how to improve na- tional and regional growth rates needed to look elsewhere and the fields of development economics and regional economics emerged respectively as more pragmatic responses to fill this vacuum. Thus, theoretical and empiri- cal models of regional growth could build upon the idea of growth poles (Perroux 1955) or cumulative causation (Myrdal 1957; Kaldor 1970). When several North-American macroeconomists returned to the issue of long-run growth in the mid 1980s, now with new tools to formulate equi- librium models with increasing returns and imperfectly competitive sectors, a revival of the field emerged starting with the influential articles by Paul Romer (1986) and Robert Lucas (1988). This literature describes macroeco- nomic outcomes in terms of microfoundations such as an intertemporal optimisation of consumption by rational and forward-looking households. However, the essence of this idea itself goes back to Ramsey (1928) and was earlier applied to growth modelling by Cass (1965) and Koopmans (1965). Parallel to the development of the new theoretical explanations, a vast literature on the empirics of growth emerged, commencing with the contri- New theories of economic growth 9 bution of Kormendi and Meguire (1985). Here the objective was not only to identify causes of growth, but also to find out whether growth rates across countries or regions converge or diverge over time. The importance of increasing returns, externalities and imperfect compe- tition for an understanding of the dynamics of economic development by means of the “New Growth Theories” has also led to two related research paradigms. One of these is the “New International Economics”, which pro- vides a reformulation of the theories of trade and trade policy (see e.g. Krugman 1988). The other is the “New Economic Geography”, which at- tempts to explain the spatial distribution of economic activity, both in terms of urban systems and in terms of regional development (see e.g. Krugman 1991; Fujita et al. 1995). The wave of “New Growth Theories” and its empirical counterpart has now reached a stage of maturity whose substantive contribution has already been assessed in special issues of major journals and general surveys (e.g. Ehrlich 1990; Stern 1991; Jones and Stokey 1992; Verspagen 1992; Romer 1994; Mankiw 1995; Jones and Manuelli 1997). There is also some dis- sent, e.g. Scott (1989) provides an alternative approach which rejects the use of the neoclassical production function. The empirical work on growth has benefited from new comparative data bases for a wide range of coun- tries in the world (e.g. Summers and Heston 1991; International Monetary Fund, various years; World Bank, various years). However, some of the conclusions regarding the determinants of growth drawn from such data ap- pear as yet rather fragile (Levine and Renelt 1992; Mankiw 1995). Theory and empirics are brought together skillfully in the textbook by Barro and Sala-i-Martin (1995) which provides an advanced, but accessible, treatment of all the major issues in theoretical models of economic growth and the re- lated empirical investigations. Thus, the present paper does not purport to provide yet another broad survey. Instead, we will focus only on the spatial aspects of the neoclassi- cal and the new growth models. A distinction is made between differences in growth rates due to spatial variations in parameters which influence growth in closed economies and causes of differences in growth rates be- tween open economies. The predictions of the models are also compared with the main conclusions of the well-established literature on regional eco- nomic development. Finally, implications for regional policies are identified briefly. Many of the neoclassical and new growth models describe accumulation in closed economies. Explanations for spatial differences in growth rates between such economies must necessarily derive from differences in param- eters, initial conditions or other exogenous variables. Closed economy ex- planations of differences in growth rates are discussed in Sect. 2. At the regional level, there is spatial interaction in terms of trade, capi- tal flows, migration, diffusion of technological innovation and information exchanges. Thus, the closed economy models can provide at best a very limited understanding of regional growth. Section 3 considers the implica- tions of introducing factor mobility, trade, economic integration and innova- 10 P. Nijkamp, J. Poot tion diffusion into models of growth. It will become clear that the exten- sion of the new growth models to the case of open economies is not yet fully satisfactory, and much work remains to be done in this area (Barro and Sala-i-Martin 1995, p. 128). Section 4 focuses on the transitional dynamics in closed or open econo- mies. An understanding of the transitional dynamics will enable predictions to be made about convergence or divergence. An assessment of the some- times contradictory empirical evidence on this matter is provided. Section 5 compares the new theories of growth with the conventional theories of regional development. While some of these have built upon neoclassical theories (as surveyed in e.g. McCombie 1988a), the post-Key- nesian perspective which puts more emphasis on the role of demand in the economy and Kaldor’s formulation of technical change (Kaldor 1957), had tended to be more popular (McCombie 1988b). The contribution, and po- tential, of evolutionary economics for an understanding of the regional growth process is also briefly addressed in this context.