Spillover of Ideas and Regional Growth in Brazil Ronaldo A. Arraes Vladimir Kühl Teles** The main focus of this paper is to provide better empirical comprehension of the income differential among brazilian regions. In the scope of the endogenous growth models framework, recent theoretical debates have relied on neo-schumpeterian models where technological innovation has provided strong evidence toward positive externalities on growth. Econometric models provide the measuring of spillovers of ideas, not only over time but also across regions, in the process of generating externalities. Two distinct conclusions were drawn from the results. First, there is evidence of a strong feedback in the R&D toward spillover over time with increasing returns in production. Secondly, it is verified a significant regionally negative spillover effect, which indicates that the production of ideas is competitive among regions, therefore, there must have comparative advantage in the regional income distribution. Key-words: Regional Growth in Brazil, Technological Innovation, Production Function of Ideas. JEL: R11, O18, O32 Graduate Program in Economics (CAEN), Federal University of Ceará, Brazil. [email protected] ** University of Brasilia, Brazil 2 Spillover of Ideas and Regional Growth in Brazil 1. Introduction Can the exponential growth be sustainable? If so, what will determine the dynamics of long-term growth? Also, what type of policies can be implemented to promote progresses in the levels of well being of the population? Such remark questions addressed a main concern in growth studies of in the 50’s and 60’s decades, which have been brought up recently by new models of endogenous growth. Two facts motivated the recent contributions to the growth theory. Firstly, the growth of the product supplanted the population growth continually during the last two centuries. Secondly, different countries and regions presented a persistent discrepancy in their growth rate relative to more developed countries and regions. Cross-sectional and time series data have presented a significant correlation between national/regional growth and several variables of economic, social and political-institutional characteristics, many of them guided directly by government politics. These observations led to the formulation of a new generation of economic growth models, which establish that the growth of income of local and global economies is a consequence of the performance of several factors of political and structural grounds. Although the motivating facts and intentions seem to be similar, it is possible to verify partitions within the recent theory of endogenous growth itself. Under that aspect, a stream of theorists understand the capital accumulation (physical and/or human 1) as the driving force for economic growth (e.g. Jones and Manuelli, 1990; King and Rebelo, 1990; Rebelo, 1991). It states that firms accumulate capital continuously in perfectly competitive market with constant returns to scale. Since capital is paid off by marginal product, the only innovation of such models refers to the imposition of an inferior limit to the private return of capital as a property of the aggregate production function in order to assure profitability of the investment. On the other hand, another approach frequently observed in the same theoretical framework is the insertion of capital external effects on production, so that as individuals accumulate capital, they contribute unwarily to the productivity of others. These spillovers are modeled, naturally, under the perspectives of both physical capital (Arrow, 1962; Romer, 1986), and the human capital (Lucas, 1988). In that stream of thought, if the spillovers are sufficiently strong, the capital marginal product can be kept continuously under the discount rate, so that growth can be maintained by a continuous accumulation of such inputs that generate positive externalities. These two approaches offer coherent explanations for stylized facts of economic growth. However, the approach on the models of endogenous growth has been the one that support the neo-schumpterian models of economic growth, where the main mechanism to that moves the economic growth process is the technological innovation. Such perspective, first theorized by Schumpeter (1934), is applied to endogenous models through a linear differential 1 It is worth pointing out here that models as the one of Mankiw et. al. (1992) establish clear that human capital can be seen as "anoother face" of the physical capital in the exogenous growth model without altering their main conclusions. So that, it is not just the insertion of human capital itself that turn the endogenous models innovative, but how this variable is treated in such models. 3 equation for the technological process. The theory is in agreement with Romer (1990), Grossman and Helpman (1991) and Aghion and Howitt (1992), which states that the economic growth is driven by the R&D sector, or sector of "ideas", of the economy. However, the differential equation that expresses the technological production, that is, the production function of ideas and inserted in these models requires a key hypothesis to explain the exponential growth in the long run: exact linearity. In that way, the applicability of those models for the explanation of the observed income differential between countries or regions depends upon the truthfulness of this hypothesis. This opposes the hypothesis of concavity of the ideas production function, as proposed by Jones (1995). This would imply decreasing returns to the R&D sector, whose immediate consequence is to zero out the rate of economic growth at the steady state, in the absence of a permanent growth of the number of workers engaged in the sector. It is based upon this theoretical motivation that this paper aims to contribute to a better understanding of the income differential among the regions of a LDC country: the case of Brazil. By estimating the regional production function of ideas, it would then become available the estimates needed to turn out possible inferences on the linearity of such a function and, consequently, on the applicability of the neo-schumpeterian models for the Brazilian regions. To make it possible, we will propose alternative econometric models seeking the estimate of the spillovers of ideas by means of panel data in order to capture timely as well as the cross-sectional inter-regional effects, to test whether or not the development of the R&D sector of a region can generate externalities on the others. 2. Theoretical Foundations 2.1. The Problem of Parameterization: Romer versus Jones While the exogenous growth models considered that the technological progress was “a gift from heaven”, recent growth models embodied a framework in the opposite direction, where the technological progress should be understood throughout a production function of ideas, represented by the following equation: (1) A H A A Where, A is the rate of technical progress, H A is the number of researchers engaged in the production of ideas, and A is the stock of ideas of the economy. The seminal work of Romer (1990) considered as hypothesis that 1 , which implies the exact linearity of the production function of ideas. That means, an increase in the stock of ideas, or the number of researchers, would bring about a perfectly proportional effect in the rate of technical progress of the economy. It is worthwhile pointing out that the magnitude of becomes crucial for the overall implications of the considered models. In this regard, if 0 , the hypothesis of fishing out in the R&D sector could not be rejected, so that the number of ideas would be limited as the number of fishes in the lake, and each new idea produced would raise the cost of an additional new possible idea; likewise, the more fishes are caught, the less amount of fishes remain in the lake. If 0 1 , the growth rate would tend asymptotically to zero. In the case if 1 , the growth rate would go up along the time, once A would tend to the infinite in a finite amount of time. 4 It should be noted that the linearity hypothesis proposed by Romer (1990), and according to equation (1) above, is expressed by, A (2) HA A In other words, the growth rate could be increased permanently while there was positive variation of H A . In opposition, Jones (1995) rejects that and proposes his hypothesis as 1 , meaning with this specification that the spillovers of ideas overtime are proportionally lower and 1. This implies that the returns to research effort are subject to some type of concavity. Under this approach, the growth rate of ideas would be given by, A H A (3) A A1 where, by taking logarithms and differentiating with respect to time, it follows that, H ( A ) HA A (4) A 1 In agreement with the expression (4), if the spillover of ideas is lower than what is foreseen by Romer, the rate of economic growth of steady state will equal zero, as long as the number of workers engaged in the R&D sector does not grow permanently. Therefore, obtaining reliable estimates on the magnitudes of and is necessary to provide support to the theoretical debate concerning the formulation of economic growth policies, either in the national extent or in the regional context. 2.2. The Production Function of Ideas in the Regional Scheme Currently, researchers have paid special attention to the fact that the production of ideas in a country can affect the production of ideas in other countries through trading or by mere imitation. It is then very plausible to expect that whichever the effect, it tends to be much stronger in a regional space where there are no barriers to trading or mobility of production inputs, once all regions are supposed to be regulated by the same legislation. Furthermore, the implications of space spillovers of ideas have been a region of intense research both in theoretical and empirical basis in the theory of the growth (e.g. Grossman and Helpman, 1991; Rivera-Batiz and Romer, 1991; Griliches, 1992; Coe and Helpman, 1995; Jones, 1995; Eaton and Kortum, 1996, 1998; Keller, 1997). The main implications of these researches are that, under the hypothesis of equality of the factors prices, which is a consequence of the spillovers of ideas, the rate of growth of backward regions is to be larger than the one of the leaders regions, therefore the convergence of income among regions is unavoidable (Abromowitz, 1986; Barro and Sala-i-Martin, 1992). The production function of ideas can also be enriched by considering that, in the regional scheme, the production of ideas in the national context promotes direct effects on the domestic ideas production of a certain region, consequently, the production function takes the following new version, (5) A j H A Aj A j where A j is the stock of ideas of region j , and A j is the stock of ideas of other regions in the country. Thus, a positive value of captures the possibility of inter-regional externality, 5 measuring the magnitude of complementarily between domestic and inter-regional knowledge. It is evident, however, that the functional form of the relationship between the productions of ideas of region j and the other regions can assume alternative formulations, as for instance, the CES specification proposed by Porter and Stern (2000): A j H A ( A j Aj ) (5') In that sense, they suggest that, although its computing is more complex, the specification according to CES furnishes qualitatively more robust results. Therefore, it stands clear that a model aiming to explain the dynamics of the R&D sector of a local economy, that is, the path of ideas growing has to take into consideration the existent relationship with the inter-regional production of ideas. 3. Empirical Tests for Brazil 3.1 Estimation Econometric models will give support to the analysis by supplying estimates these will generate inferences on the linearity of the production function of ideas for regions of Brazil. If so, such models are constituted to estimate the parameters of the functions above discussed, that is, (6) A H A A (7) A j H A A j A j (8) A H ( A A ) j A j j whose theoretical interpretations were detailed in section 2. The estimation of equation (6) has as central objective to predict the dynamic spillovers in the production of ideas inside of each state, while the estimations of equations (7) and (8) aim the observation of the inter-state spillovers for idea production. Initially, two estimation methods are proposed, the ordinary least square for equations (6) and (7) by applying logarithm on both sides, and the second method is the two stage non-linear least square for all three equations. Moreover, after testing for homoscedasticity, another method of estimation – autoregressive model conditioned to heteroscedasticity – will be performed so that to exhaust all necessary estimation possibilities, in order to obtain better reliability of the results. First the equations are estimated for a sample containing all of the Brazilian states, and afterwards, separate estimates are accomplished for each aggregate region of the country. In both cases, the procedure will deal with panel data, so that it will be able to test for spillovers occurrence with different magnitudes, when considered the national and regional grounds in separate forms. In doing so, it will be possible to withdraw information on convergence clubs formation among regions. 3.2. Data The proxy used for measuring the stock of ideas is the number of patents registered by each state, where the main data source is the National Institute of Patents and Inventions (NIPI). Concerning a proxy for the number of researchers producing ideas, several alternative 6 measures were tested, where the one chosen due to better adjustments to the models was the average of schooling years of the population2. Data are used in annually time series from 1979 to 1995. Since it is considered the inexistence of depreciation of the stock of ideas, data for 1979 refer to the sum of the patents registered in all of the previous periods, and for every year was added up the number of registered patents, thus accumulating the stock of ideas of each state/region, so that the series is non-decreasing. In this respect, the evolution of the frequency distribution of the stocks of ideas is presented concisely in table 1. Table 1 Frequency of the Stock of Ideas in Brazil, by Regions, 1979-1985 Regions North Northeast Southeast South Mid-West Years 1979 0,00 10,69 87,92 1,21 0,18 1985 0,00 20,69 77,87 1,35 0,09 1990 0,00 20,53 78,10 1,29 0,08 1995 0,03 9,44 88,17 2,31 0,05 Source: NIPI. Table 2 Growth of the Stock of Ideas in Brazil by Regions (base year: 1979=100) Regions North Northeast Southeast South Mid-West Years 1979 100,00 100,00 100,00 100,00 100,00 1985 100,00 253,14 116,19 138,41 100,00 1990 100,00 277,88 128,55 144,85 100,00 1995 338,70 295,78 289,21 177,27 100,00 Source: NIPI Two remarkable facts can be pointed out from the regional distribution of the stock of ideas, in agreement with the results of table 1. First, there is strong evidence of centralization of the stock of ideas in the Southeast, ranging from 75% to 90% of the total stock of ideas of the country during the analyzed period. Second, the region closest to the Southeast in producing ideas is the Northeast, which seemed to converge to the former region in the 80’s, however it started a diverging process in the beginning of the next decade. The explanation 2 In view of unavailability of a source of information for the correct specification of the variable in the model (H), number of producing of ideas, it is believed that the proxy here used keeps a high positive correlation with the variable H. 7 for such divergence can be found in the economic opening by which the country passed through the 90’s which could have promoted a more direct effect on the southeastern region, the richest one. Table 2 reinforces such facts, where an index is built for each region, with the purpose of observing the dynamics of the stock of ideas growth in elapsing time. It is clear from such data that no patent was registered in any state of the Mid-West in the whole period, the same happening with the North during the 80´s. Besides, two periods stand out on the growth of the stock of ideas in two regions; the beginning of the 80’s decade in the Northeast, and the beginning of the 90’s decade in the Southeast. Therefore, in view of this characterization of the data, the focus of regional analysis will be driven to the Southeast, Northeast, and including the South for being the second most developed region. These regions account for the almost totality of the stock of ideas of the country. 3.3. Estimates Tables 3 to 5 present the results of the estimates of equations (6) to (8), respectively, starting from the data contained in panel for all of the Brazilian states in the analyzed period, by applying the methods of ordinary least squares (OLS), two stage non-linear least squares (TSNLS) and autoregressive models conditioned to heteroscedasticity (ARCH)3. Table 3 Estimations of Equation (6) – Brazil Parameters R2 F OLS -0,5831 (0,39) 0,6272* (0,28) 0,9173* (0,01) 0,85 1125,60 Models TSNLS 0,9157* (0,34) 1,0946* (0,10) 0,8484* (0,03) 0,84 1672,22 ARCH -0,6945* (0,40) 0,6659* (0,29) 0,9295* (0,04) 0,85 446,08 Notes: Values in parenthesis are standard errors.. (*) Significant up to 5%. 3 Although the OLS estimators are inefficient in the presence of heteroscedasticity, theirs estimates are kept among the results just to illustrate such inefficiency. 8 Table 4 Estimations of Equation (7) – Brazil Parameters R2 F OLS 8,9278* (4,09) 0,6359* (0,27) 0,9064* (0,02) -0,7767* (0,33) 0,85 760,85 Models TSNLS 59,0409 (48,97) 1,0339* (0,11) 0,7467* (0,03) -0,2505* (0,04) 0,85 1218,43 ARCH 14,0665* (3,15) 0,6270* (0,23) 0,9614* (0,02) -1,2220* (0,24) 0,85 361,87 Notes: Values in parenthesis are standard errors. (*) Significant up to 5%. Table 5 Estimates of Equation (8) by TSNLS – BRASIL Parameters TSNLS 2,85E-05 (3,56E-05) 1,4401* (0,15) 7,1752* (1,10) 1,2359* (0,12) 0,65 262,11 R2 F Notes: Values in parenthesis are standard errors.. (*) Significant up to 5%. The results presented in table (3) show inference on the parameters of the production function of ideas according to the original theoretical model. The estimates from OLS and TSNLS do not allow inferring about the linearity of such function. It indicates, however, a strictly concave function, exhibiting decreasing marginal returns regarding the existent stock of ideas, as the appropriate statistical tests are carried out, and the hypothesis that 1 cannot be rejected for any one of the estimation methods, while the hypothesis that 1 the is rejected at a significance level of up to 5% for both estimates. 9 However, it should be emphasized that the use of panel data itself already provides the expectation for the heteroscedasticity occurrence, which might be confirmed by inspection of the data disposition, especially regarding the variable number of researchers and, formally, by performing White’s test. As so, it is expected that the estimates by OLS tend to present some type of bias when accomplishing inferences on the parameters of the regression. Therefore it is necessary to run estimations throughout autoregressive models conditioned to heteroscedasticity. The results reached from this regression, unlike the previous ones, lead to the non-rejection of the linearity of the production function of ideas, so that both and are not statistically different from 1. In other words, the empirical evidences obtained from the model corrected to heteroscedasticity point for the non-rejection of the hypothesis proposed by Romer (1990), Grossman and Helpman (1991), Aghion and Howitt (1992), regarding the scale effects of the R&D sector as the main power for economic growth, whereas it is verified the dynamic spillover effect of this sector for the Brazilian case. Nonetheless, it is yet to be tested for the occurrence of regional spillovers of R&D, through the estimates of equations (7) and (8), presented in tables 4 and 5. The estimates shown in table 4 corroborate with the conclusions obtained from the previous results, where the hypothesis that 1 cannot be rejected in none of the estimations and the hypothesis that 1 cannot be rejected either, when the correction for heteroscedasticity is accomplished. However, all of the estimates present a negative result in accordance to the test of regional spillover in the sector of ideas. It indicates that, although the innovations have a complementary characteristic with future innovations, they point for a substitute scenario concerning innovations of other regions, endorsing, therefore, the hypothesis of fishing out in the process of regional distribution of ideas. These results are of extreme relevance on the theoretical discussion that involves the convergence hypothesis, contrary to what is predicted thoroughly by convergence models, (Barro and Sala-i-Martin (1995)), where regions possessing a research sector less developed do not tend to approach their growth to those regions with research sector more developed. This suggests an inter-regional competition in the R&D sector, so that development in a certain region promotes an endogenous positive scale effect of it, but negative in relation to the other regions. A relevant question to be highlighted is: Under which regional extent the development of the R&D sector does not generate positive externalities, turning to implicate in negative externalidades on the sector of some other places? In order to shed light on this question, the equation (7) has been reestimated to each one of the regions with the largest participations in R&D of the country (Southeast, Northeast and South), generating estimates presented in tables 6 to 8. 10 Table 6 Estimations of Equation (7) – Southeast Parameters R2 F OLS -0,0038 (0,04) 2,3418* (0,57) 0,9418* (0,02) -0,4007* (0,07) 0,95 3050,64 Models TSNLS 0,0225 (0,01) 1,1702* (0,17) 1,0352* (0,03) -0,4745* (0,04) 0,95 1351,12 ARCH 0,0013 (0,96) 1,9623* (0,22) 0,7325* (0,01) -0,5625* (0,08) 0,92 846,62 Notes: Values in parenthesis are standard errors.. (*) Significant up to 1%. Table 7 Estimations of Equation (7) – South Parameters R2 F OLS -0,0007 (0,02) 5,0534* (0,60) 0,6213* (0,02) -0,4544* (0,06) 0,95 2810,59 Notes: Values in parenthesis are standard errors.. (*) Significant up to 5%. Models TSNLS 55,0667 (40,24) 1,8116* (0,15) 0,7703* (0,04) -0,4316* (0,06) 0,95 2644,99 ARCH 0,0034 (1,005) 6,0814* (0,54) 0,3458* (0,01) -0,4195* (0,10) 0,92 795,5 11 Table 8 Estimations of Equation (7) – Northeast Parameters R2 F OLS 0,0039 (0,07) 1,7640* (0,37) 0,8571* (0,02) -0,1132* (0,03) 0,86 845,56 Models TSNLS 5527,57 (6153,33) 1,8080* (0,19) 0,7183* (0,04) -0,6597* (0,11) 0,84 719,23 ARCH 0,0120 (1,86) 2,7096* (0,23) 0,5671* (0,02) -0,1096 (0,13) 0,80 265,74 Notes: Values in parenthesis are standard errors.. (*) Significant up to 5%. The results observed in the tables 6 to 8 indicate to be relevant, since the inference on the convergence of the sector of ideas cannot be verified, not even inside of a specific region, which also rejects the hypothesis of convergence blocks. Another estimation procedure was conducted, where the causal factor that dictates the existence cross-section spillover effect was specified through iterative dummies variables for each region, so that it is assumed by this formulation that the coefficients , and remain constant independently of the considered region, thus testing the hypothesis that just the space spillover varies indeed from region to region. The results of such model are presented in table 9. As observed previously, the results presented in table 9 implicate a negative space spillover in the R&D sector of any Brazilian region, corroborating the hypothesis of regional fishing out. Such results meet the convergence theories based upon the arguments that the cost of imitating a technology is lower than the cost of producing an innovation. On the other hand, the results here found implicate that to each innovation, the innovative region generates a scale effect on its future productivity, however it does not promote or obstruct the capacity of innovation of the other regions, so that the regional convergence should be better understood through the mobility of production factors than the mobility of ideas. 12 Table 9 Estimations of Equation (7) – Regional Effects Parameters (North) (Northeast) (Southeast) (South) (Mid-West) R2 F Models OLS 5,6285 (3,88) 2,2477* (0,41) 0,7841* (0,02) -0,7962* (0,32) -0,5943* (0,30) -0,5875* (0,32) -0,6270* (0,31) -0,7850* (0,32) 0,87 394,22 ARCH 12,4418* (0,36) 1,7045* (0,05) 0,7519* (0,006) -1,3167* (0,03) -1,1118* (0,03) -1,0669* (0,03) -1,0944* (0,03) -1,2285* (0,03) 0,87 260,47 Notes: Values in parenthesis are standard errors.. (*) Significant up to 5%. Conclusions The central debate regarding the new theories of economic growth has been centering on the rule of the sector of "ideas" of an economy. Under such aspect, the neo-shumpeterian models of growth, as for instance, Romer (1993), Grossman and Helpman (1991) and Aghion and Howitt (1992) suggest that the growth of the productivity is driven by a constant allocation of resources for a producing sector of ideas, where such result critically depend upon positive and especially strong dynamic spillovers, modeled through a production function of ideas. Such an assessment has been under investigation, motivated by some alternative models as that of Jones (1995), which inserts the hypothesis of decreasing returns in the production function of ideas. Within this debate, this paper aimed to contribute to the empirical understanding, still not much explored, of the behavior of the production function of ideas in a developing country – the case of Brazil – taking as central focus of analysis a regional overview. The paper provided evidence for two main questioning. First, it is emphasized that the results obtained from the estimates accomplished with data at state level support the existence of a strong feedback in the R&D sector, as proposed by Romer (1990), being evidenced by the linearity of the production function of ideas, and, therefore, the existence of a positive dynamic spillover in the research activity. Second, contrary to the dynamic approach, which investigated the existence of a regional spillover of innovations in the R&D sector, it was also verified the existence of a significant negative regional spillover, so that, while an innovation implicates in scale effects 13 in the sector of research within a specific region – assuming a complementary characteristic with future research – it has an adverse impact on the sector of the other regions, assuming substitute effect under the regional point of view. Such results allow inferring that innovations might be considered specific assets to each place. From the results obtained by estimation, and following the reasoning of Romer (1990), among others, increasing returns seem to be a fact by nature. Ideas are a central factor in the world we live. Under a time series standpoint, ideas are non-rivals, that implicates increasing returns to scale naturally. 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