Does the internet generate economic growth, international trade, or both? Huub Meijers

Similar documents
Marketing Mix Modelling and Big Data P. M Cain

FORECASTING DEPOSIT GROWTH: Forecasting BIF and SAIF Assessable and Insured Deposits

The Contribution of Human capital to European Economic Growth: An empirical exploration from a panel data

16 : Demand Forecasting

Stock market booms and real economic activity: Is this time different?

TEMPORAL CAUSAL RELATIONSHIP BETWEEN STOCK MARKET CAPITALIZATION, TRADE OPENNESS AND REAL GDP: EVIDENCE FROM THAILAND

SYSTEMS OF REGRESSION EQUATIONS

Trade, Finance, Specialization and Synchronization: Sensitivity Analysis

Chapter 4: Vector Autoregressive Models

Testing for Granger causality between stock prices and economic growth

FDI as a source of finance in imperfect capital markets Firm-Level Evidence from Argentina

A Short review of steel demand forecasting methods

Testing The Quantity Theory of Money in Greece: A Note

The Effect of Prison Populations on Crime Rates

Do R&D or Capital Expenditures Impact Wage Inequality? Evidence from the IT Industry in Taiwan ROC

Lecture 12 The Solow Model and Convergence. Noah Williams

THE IMPACT OF MACROECONOMIC FACTORS ON NON-PERFORMING LOANS IN THE REPUBLIC OF MOLDOVA

The VAR models discussed so fare are appropriate for modeling I(0) data, like asset returns or growth rates of macroeconomic time series.

THE CONTRIBUTION OF ECONOMIC FREEDOM TO WORLD ECONOMIC GROWTH,

Is the Forward Exchange Rate a Useful Indicator of the Future Exchange Rate?

ESTIMATING AN ECONOMIC MODEL OF CRIME USING PANEL DATA FROM NORTH CAROLINA BADI H. BALTAGI*

Export Pricing and Credit Constraints: Theory and Evidence from Greek Firms. Online Data Appendix (not intended for publication) Elias Dinopoulos

An Analysis of the Telecommunications Business in China by Linear Regression

IT Productivity and Aggregation using Income Accounting

Corporate Taxes, Profit Shifting and the Location of Intangibles within Multinational Firms

2013 MBA Jump Start Program. Statistics Module Part 3

VI. Real Business Cycles Models

A Panel Data Analysis of Foreign Trade Determinants of Nepal: Gravity Model Approach

COURSES: 1. Short Course in Econometrics for the Practitioner (P000500) 2. Short Course in Econometric Analysis of Cointegration (P000537)

Auxiliary Variables in Mixture Modeling: 3-Step Approaches Using Mplus

Markups and Firm-Level Export Status: Appendix

Current account core-periphery dualism in the EMU. Tatiana Cesaroni (Bank of Italy) and Roberta De Santis (Istat)

Do Supplemental Online Recorded Lectures Help Students Learn Microeconomics?*

Monetary policy rules and their application in Russia. Economics Education and Research Consortium Working Paper Series ISSN

ANNEX 1 - MACROECONOMIC IMPLICATIONS FOR ITALY OF ACHIEVING COMPLIANCE WITH THE DEBT RULE UNDER TWO DIFFERENT SCENARIOS

Chapter 5: Bivariate Cointegration Analysis

A Primer on Forecasting Business Performance

This PDF is a selection from an out-of-print volume from the National Bureau of Economic Research

From the help desk: Bootstrapped standard errors

TAX EVASION AND SELF-EMPLOYMENT OVER TIME: EVIDENCE FROM SWEDEN

International and national R&D outsourcing: Complements or substitutes as determinants of innovation?

Conditional guidance as a response to supply uncertainty

What s New in Econometrics? Lecture 8 Cluster and Stratified Sampling

Nontechnical Summary

Earnings in private jobs after participation to post-doctoral programs : an assessment using a treatment effect model. Isabelle Recotillet

2. Simple Linear Regression

Relationship among crude oil prices, share prices and exchange rates

CONVERGENCE OF INCOME ACROSS PENNSYLVANIA COUNTIES

Determinants of Capital Structure in Developing Countries

Higher Education and Economic Growth in Africa

8.1 Summary and conclusions 8.2 Implications

The US dollar exchange rate and the demand for oil

Introduction to Regression and Data Analysis

2. Linear regression with multiple regressors

Overview of Violations of the Basic Assumptions in the Classical Normal Linear Regression Model

Mortgage Loan Approvals and Government Intervention Policy

Employer-Provided Health Insurance and Labor Supply of Married Women

Least Squares Estimation

Department of Economics

Chapter 5 Estimating Demand Functions

Insurance and the Macroeconomic Environment

An Analysis of the Effect of Income on Life Insurance. Justin Bryan Austin Proctor Kathryn Stoklosa

Online Appendices to the Corporate Propensity to Save

Stress-testing testing in the early warning system of financial crises: application to stability analysis of Russian banking sector

DEPARTMENT OF ECONOMICS CREDITOR PROTECTION AND BANKING SYSTEM DEVELOPMENT IN INDIA

Cost implications of no-fault automobile insurance. By: Joseph E. Johnson, George B. Flanigan, and Daniel T. Winkler

Panel Data Econometrics

Currency Unions and Irish External Trade. Christine Dwane Trinity College Dublin. Philip R. Lane, IIIS, Trinity College Dublin & CEPR

Optimal education in times of ageing: The dependency ratio in the Uzawa Lucas growth model Anne Edle von Gaessler and Thomas Ziesemer

THE EFFECTS OF TRADE LIBERALIZATION ON THE ENVIRONMENT: AN EMPIRICAL STUDY

Chapter 5: Analysis of The National Education Longitudinal Study (NELS:88)

PROJECTION OF THE FISCAL BALANCE AND PUBLIC DEBT ( ) - SUMMARY

STATISTICA Formula Guide: Logistic Regression. Table of Contents

Determinants of Stock Market Performance in Pakistan

Panel Data Analysis in Stata

EFFECTS OF TAX POLICY ON ECONOMIC GROWTH IN OECD COUNTRIES

The impact of exports on economic growth: It s the market. form

Measuring BDC s impact on its clients

INDIRECT INFERENCE (prepared for: The New Palgrave Dictionary of Economics, Second Edition)

Does Debt Relief enhance Growth in Third World Countries?

What Drives a Successful Fiscal Consolidation?

Exploring Interaction Between Bank Lending and Housing Prices in Korea

ADVANCED FORECASTING MODELS USING SAS SOFTWARE

Determinants of demand for life insurance in European countries

Chapter 4 Technological Progress and Economic Growth

Chapter 6: Multivariate Cointegration Analysis

PITFALLS IN TIME SERIES ANALYSIS. Cliff Hurvich Stern School, NYU

The effect of the Internet on regional integration: evidence from China

An Empirical Analysis of Determinants of Commercial and Industrial Electricity Consumption

5. Multiple regression

FOREIGN TAXES AND THE GROWING SHARE OF U.S. MULTINATIONAL COMPANY INCOME ABROAD: PROFITS, NOT SALES, ARE BEING GLOBALIZED.

This content downloaded on Tue, 19 Feb :28:43 PM All use subject to JSTOR Terms and Conditions

FIXED EFFECTS AND RELATED ESTIMATORS FOR CORRELATED RANDOM COEFFICIENT AND TREATMENT EFFECT PANEL DATA MODELS

Asian Economic and Financial Review DETERMINANTS OF THE AUD/USD EXCHANGE RATE AND POLICY IMPLICATIONS

IS THERE A LONG-RUN RELATIONSHIP

Additional sources Compilation of sources:

COMMISSION OPINION. of XXX. on the Draft Budgetary Plan of ITALY

Yao Zheng University of New Orleans. Eric Osmer University of New Orleans

Figure 1.1 The Parade of World Income. Copyright 2005 Pearson Addison-Wesley. All rights reserved. 1-1

This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and

Transcription:

Working Paper Series #2012-050 Does the internet generate economic growth, international trade, or both? Huub Meijers Maastricht Economic and social Research institute on Innovation and Technology (UNU MERIT) email: info@merit.unu.edu website: http://www.merit.unu.edu Maastricht Graduate School of Governance (MGSoG) email: info governance@maastrichtuniversity.nl website: http://mgsog.merit.unu.edu Keizer Karelplein 19, 6211 TC Maastricht, The Netherlands Tel: (31) (43) 388 4400, Fax: (31) (43) 388 4499

UNU-MERIT Working Papers ISSN 1871-9872 Maastricht Economic and social Research Institute on Innovation and Technology, UNU-MERIT Maastricht Graduate School of Governance MGSoG UNU-MERIT Working Papers intend to disseminate preliminary results of research carried out at UNU-MERIT and MGSoG to stimulate discussion on the issues raised.

Does the internet generate economic growth, international trade, or both? Huub Meijers, May 2012 Abstract Recent cross country panel data studies find a positive impact of internet use on economic growth and a positive impact of internet use on trade. The present study challenges the first finding by showing that internet use does not explain economic growth directly in a fully specified growth model. In particular openness to international trade variables seems to be highly correlated with internet use and the findings in the literature that internet use causes trade is confirmed here, suggesting that internet use impacts trade and that trade impacts economic growth. A simultaneous equations model confirms the positive and significant role of internet use to openness and the importance of openness to economic growth. Internet use has been shown to impact trade more in non high income countries than in high income countries, whereas the impact of trade on economic growth is the same for both income groups. JEL classification: C23, L86, F10, O40 Keywords: economic growth, internet, trade, panel Acknowledgement The author is grateful to the participants of the ICTNET workshop in Parma for a useful discussion and to Thomas Ziesemer for his critical comments and suggestions. The usual disclaimer applies. UNU MERIT and Department of Economics, Maastricht University, the Netherlands. huub.meijers@maastrichtuniversity.nl 1

I. Introduction This paper is an empirical investigation on the relation between international trade, internet use and economic growth. Recent literature shows a positive and causal relation between internet use and international trade whereas other papers demonstrate a positive relation between internet use and economic growth. There is also a lively debate on the relation between international trade and economic growth and the mainstream finding in this debate concludes that trade positively impacts economic growth but particular results depend on econometric techniques, country sample, and time period. The main question addressed in this paper is whether internet use has a direct impact on economic growth or whether internet use impacts economic growth more indirectly through trade. Secondly the literature finds that internet use impacts international trade more in non high income countries than in high income countries and we investigate this by employing the final empirical model as applied to the total sample of countries to high and on high income countries separately. The starting point is the literature on economic growth as pioneered by (Solow, 1956) and employed in empirical work by e.g. (Barro, 1991; Barro, 2003), (Quah, 1993; Quah, 1997), (Islam, 1995), (Bosworth and Collins, 2003) and many others. The next section elaborates on this by portraying a standard basic growth equation relating economic growth (as measured by the growth rate of per capita GDP) to per capita internet use and several control variables and allowing for long run growth rates to be country specific by including individual country intercepts. After a brief discussion of the data the first empirical analysis supports the initial view that economic growth is positively related to internet use as found by for instance (Choi and Hoon Yi, 2009). A more detailed analysis however shows that this conclusion has to be relaxed and that internet use does not seem to impact economic growth in a direct way. If standard control variables such as investment, government expenditure, rate of inflation and openness are included and also if time dummies are included to capture longitudinal variation, internet use does not seem to have a positive contribution to economic growth. Leaving out internet use re establishes the traditional growth equation whereby, amongst others, openness as a measure of international connectedness of countries has a positive and significant impact on economic growth. (Clarke and Wallsten, 2006), (Freund and Weinhold, 2004) and (Vemuri and Siddiqi, 2009) all study the impact of internet use on international trade and they all find a 2

positive relation between internet use and trade, although not as strong for all regions. In the tradition of empirical trade models a gravity approach is employed using bilateral trade data. 1 So the natural question emerges whether internet use impacts economic growth or international trade and whether international trade impacts economic growth or internet use. Section 4 discusses a Granger causality analysis on this issue by using a VAR analysis on economic growth, international trade and internet use showing that internet use is Granger causing trade whereas per capita GDP does not and that the relation of internet use causing international trade is stronger than the other way around. This is somewhat relaxed by a similar analysis if time dummies are included but also here internet use is impacting trade more significantly than the other way around and international trade impacts economic growth more significantly than internet use. Combining the findings from the growth equation from section 3 and the Granger causality analysis suggest a direct relation between international trade and economic growth and a direct relation between internet use and international trade. Section 5 shows that indeed internet use has a positive impact on international trade as reported in the literature. The trade model includes amongst others the area size of countries which is fixed over time. This demands a model combining notions from a panel fixed effects model with time invariant variables. Three different approaches are investigated all leading to the same conclusion that internet use is positively affecting international trade. Finally, section 6 elaborates on this by suggesting a simultaneous equation model whereby both the growth rate of per capita GDP and openness, measured as imports plus exports as ratio of GDP, are explained. International trade is positively and significantly related to economic growth and internet use indeed appears to be positively and significantly related to openness. This leads to the suggestion that internet use is not impacting economic growth in a direct way but though international trade. (Clarke and Wallsten, 2006) and (Clarke, 2008) study the impact of internet use on international trade in developed and in developing countries and conclude that this effect is much more emphasized in developing countries than in developed countries. The second part of section 6 resembles their analysis by employing the simultaneous equation approach and finds that the impact of international trade on economic growth is not different at all between low and high income countries. However, that seems not 1 (Clarke and Wallsten, 2006) employ a broad quasi bilateral trade setting by differentiating exports from countries to high income countries and to low income countries. 3

to be the case for the impact of internet use on international trade where we indeed find significant differences between high income and non high income countries. II. Economic Growth and internet use The internet can be regarded as a truly general purpose technology and impacts society at various levels and in a vast range of activities ((Harris, 1998)). 2 Firms are able to communicate better, faster and at lower costs, reducing internal as well as external transaction costs and thus lowering production costs and enhancing productivity and generating economic growth. The internet facilitates the generation and spread of knowledge and new ideas tremendously which allows for an increased productivity of the research process and an increased diffusion of its products and outcomes. The internet also affects markets such as the labour market ((T. Ziesemer, 2002), (Stevenson, 2008)) and the product market ((Levin, 2011)) by reducing search costs and facilitating access to information. Conversely internet also impacts society in a less positive way as for instance online crime is spreading rapidly ((Moore et al., 2009)). Models on endogenous growth theory focus on the importance of increasing returns, R&D activities, human capital, the generation and spread of new ideas, and the diffusion of new technologies in general on economic growth. ((Lucas, 1988; Romer, 1990; Aghion and Howitt, 1992)). In this context new communication technologies like the internet not only may reduce marginal costs of production processes but also may enhance the creation and spread of new ideas. This implies that the nature of the R&D process itself and the spread of the resulting knowledge has been changed by the use of new communication technologies like the internet ((Röller and Waverman, 2001; Czernich et al., 2011)). This suggests that the use of the internet not only induces temporary growth towards a higher level of the steady state, it also introduces the likelihood of permanent higher growth rates as the R&D process itself is affected. From that perspective it is highly relevant to test whether indeed internet use has an impact on the rate of economic growth. For this purpose we will include internet use in empirical growth models as to investigate its importance for economic growth. 2 The term internet used here refers not only to the physical infrastructure but also to the applications running on top of this infrastructure such as world wide web, email, and file transfer. 4

Closely related to studying impacts of internet use on economic growth are studies on the impact of the broader concept of information and communication technologies (ICTs) on economic growth. In the latter domain many studies have indeed shown that ICTs have a positive impact on economic growth, on labour productivity growth and on total factor productivity growth ((Jorgenson et al., 2008; Ark et al., 2008; Oliner et al., 2008)). These studies are centred on growth accounting methodologies or on estimating extended production functions which all rely on stocks for ICT and non ICT capital. In studying the impact of internet on economic growth this approach is less obvious since there are no measures of the stock of internet capital and, more important, internet as a general purpose technology is highly interconnected with many other activities such that a separation becomes less obvious but also less meaningful. The focus of this paper is on the impact of internet use and our approach is closely related to approaches in empirical endogenous growth models. The economic growth model employed here stems from (Barro, 1991) who shows that the basic neoclassical model as proposed by e.g. (Solow, 1956) and (Koopmans, 1963) should be relaxed by introducing conditional convergence entailing that the growth rate of a country depends on its initial deviation of per capita GDP from its own steady state level and thus implying that poor countries will not grow faster per se but that the growth rate depends on the distance between the initial situation and its (individual) steady state level of per capita GDP. As new technologies are not readily available in all countries or cannot be employed to their full extent differences in technological adoption and in the knowledge base may also lead to different growth rates, even if there exist diminishing marginal returns from single factors of production like capital. So whereas the Solow model explains absolute convergence all countries grow to a single steady state (Barro, 1991) and (Barro and Sala I Martin, 1991) adopt the notion of conditional convergence where steady state growth levels may differ between countries and depend on the country s technological potentials. Both the Solow model as the model employed by Barro are based on exogenous technological change. As a variant of the AK model, which is the most simple model explaining positive economic growth in a steady state, (Acemoglu and Ventura, 2002) develop a model that can explain convergence in growth rates by linking growth to international trade. This path will be further explored below. 5

Many studies in the realm of empirical economic growth models and those contributing to the discussion on economic convergence are based on the impact of new technologies, human capital and diffusion of knowledge on growth and convergence and most employ models where growth of GDP per capita is explained by various factors like savings, education, government intervention, and international trade as to differentiate between technological potentials of countries which define steady state growth levels and the dynamics towards steady states (see e.g. (Barro, 1991), (Barro, 2003), (Quah, 1993), and (Bosworth and Collins, 2003)). The basic model employed here is in line with (Barro, 1991) and (Barro, 2003) postulating a generalized growth equation as:,,, (1) where,, and where, denotes the growth rate of per capita GDP ( ) of country i at time t and, denotes a multidimensional vector of explanatory and control variables. denotes a vector of coefficients of which its elements are assumed to be identical for all countries but could have an individual dimension in a more general setup. Next to the remainder idiosyncratic disturbance term (, ), the error term, may contain an individual effect ( ) and/or a time effect ( ) leading to a one way or two way error component model, respectively. The literature on empirical growth analysis listed above includes the lagged level of GDP per capita, investment as ratio to GDP, government expenditures as ratio to GDP, the level of inflation, openness, human capital variables, and life expectancy as explanatory variables. Lagged GDP per capita reflects the convergence hypotheses and is expected to have a negative sign as low income countries are expected to show higher growth rates and thus are expected to catch up relative to high income countries, ceteris paribus. Higher rates of investment (as ratio to GDP) are expected to have a positive impact on per capita GDP growth since a higher value of the investment ratio raises the steady state level of per capita output resulting into higher growth rates, at least in the short and medium run. Investment may also be seen as carrier of new technologies (the embodiment hypothesis) leading to increased economic growth. Government expenditures include amongst others nonproductive expenditures that can distort private decisions and thus are expected to have a negative impact on per capita growth of GDP. The openness ratio as measured by imports plus exports as ratio of GDP is expected to catch the benefits coming from 6

international trade. These benefits can have different sources as international trade may reflect that a country is being linked to and integrated in the international community and therefore having access to new knowledge and to new technologies. On the other hand openness indicates access to foreign markets and may increase market size (and therefore benefits from further specialisation). In the latter case one would expect that small countries may gain more from trade since trade may increase market size relative to the home market relative more substantial in small countries than in large countries with a larger home market. Higher levels of human capital are associated with more efficient production processes higher steady state levels of per capita GDP and the ability to adopt and use more advanced technologies and thus to have a positive impact on catching up. Enrolment rates into education have been studied in empirical growth models by e.g. (Krueger and Lindahl, 2001) and, albeit in a different setting by (Ranis et al., 2000), and show to have a positive and significant impact on economic growth. The inflation rate is added as a measure of macroeconomic stability and thus is expected to have a negative sign on per capita economic growth. In order to determine the impact of internet use on economic growth next section implements equation (1) empirically using per capita internet use as additional variable. In most empirical implementations of growth equations fairly long time series are employed and in many cases averaged data are used to cancel out temporary effects and business cycles. Typical is to use averaged data over periods of five years and covering a time period from 1960 (or earlier) onwards. In order to analyse the impact of internet use on economic growth it is not straightforward to apply this strategy since data on internet use are for most countries only available from 1995 and onwards resulting in one or two data points for most countries if we would use five yearly averaged data. Using lags as instruments or including growth rates is nearly impossible in such case and this paper therefore employs yearly data covering a time period from 1990 onwards. This incorporates a risk that also cyclical effects enter the analysis but by using time dummies we try to cancel out influences of cycles at a global level. III. Data and first estimation results Data for initially 213 countries were collected from the World Bank 2010 database on World Development Indicators from 1990 until 2008 which also includes data from the International Telecommunication Union. Not all series are equally available for all countries and for the entire time period and the employed dataset includes 162 7

countries. This unbalanced dataset includes time series length varying between 1 to 18 data points per variable of a country. Table 1 summarizes the data and shows that the number of data points (N) varies considerable for different variables with an average series length between 14 and 19 data points. Most restrictive is data on internet use with an average time series length of 15 years where most missing data are observable in the early nineties. 3 [Insert Table 1 about here] In this table the overall statistics refer to the entire sample of N observations whereas the between statistics refer to the country averages. The within statistics are based on the deviations from the country averages but corrected for the overall average. If the between standard deviation and the within standard deviation are about equal, which is the case for e.g. gross fixed capital formation as percentage of GDP (investment ratio) the longitudinal variation per country is about the same as the cross section variation on country averages. In other words this implies that when drawing investment ratio data for two countries randomly from the dataset the difference between these data points is nearly equal to the difference when drawing two randomly selected years for the same country. The between and within variations for per capita internet use and for government final consumption ratio are also approximately equal. On the other hand per capita GDP and more obviously population and land area show small within variations as compared to between variations. Below we will come back to these differences of between and within variations. The measure on internet use is defined here per capita and stems from the International Telecommunication Union (ITU) where a user is defined as a person that has accessed the internet in the last 12 month and which includes access through all devices. In many cases this number is based on household surveys but may also be based on estimates by ITU where no survey data are available. See e.g. (United Nations, 2011). Other studies employ the number of internet hosts (Clarke and Wallsten, 2006) or domain names (Freund and Weinhold, 2004) as proxy for internet use but that measure might be biased because one single host (i.e. a computer connected to the internet) might be used by more people. Earlier studies report estimates of 2.5 to 4 users per hosts, a number 3 Initially also net barter terms of trade, life expectancy, fertility rates are employed but these variables did not yield satisfactory results and are not displayed in the table. 8

which might be higher in newly emerging countries such as those in Africa (International Telecommunication Union, 1997) and therefore biasing estimates for these countries. Per capita internet use is on average 12% over the entire sample, ranging from 0% to 90%. The fact that within and between variations are not that different for per capita internet use does not consequentially mean that there is no path dependency. It highlights here that the variation of internet use over the years from 1990 until 2008 is about equal to the variation of the average use over countries. Countries with high proportions of internet users per capita (above 80%) in the second half of the 2000 s are Denmark, Finland, Island, the Netherlands, Norway, and Sweden. In 32 countries the per capita internet use is below 5% in 2008 from which 23 are located in Sub Saharan Africa and from which 19 countries belong to the group of low income countries, 12 are lower middle income countries and one is a high income country (Equatorial Guinea). 4 Figure 1 on the diffusion of internet users displays the number of countries for which the percentage of internet users has passed various thresholds. 19 countries report a percentage of internet users of strictly larger than zero in 1990 and this numbers grows very fast to 114 countries in 1995 and to 160 countries in 1999. Using higher thresholds shows that one country (Island) passed the 5% threshold in 1994 and 59 countries had passed this threshold six years later. In 2008 in 15 countries the number of internet users exceeded 75%. Worldwide per capita internet diffusion started at a low 0.05% in 1990 and increased towards 6.8% in 2000 and has reached almost the 25% level in 2008. The growth rate of the percentage of internet users is still increasing in 2008 implying that the (global) inflection point is not reached. 5 [Insert Figure 1 about here] Figure 2 depicts the relation between (the log of) per capita internet use and (the log of) per capita GDP for 162 countries in 2000 and in 2008. The fast diffusion of internet use becomes apparent by the upwards shift of the data points and which is highlighted by the linear regression lines applied to both years. In this log linear relation the constant 4 These 32 countries are BGD, BEN, BFA, BDI, KHM, CMR, CAF, TCD, COG, CIV, DJI, GNQ, ETH, GHA, GIN, GNB, IND, LSO, MDG, MWI, MLI, MRT, MOZ, NPL, NIC, NER, PNG, RWA, SLE, SLB, TZA, and YEM. 5 In 2010 the percentage of internet users has increased to 30.5% and the annual growth rate is still increasing. 9

term increased between 2000 and 2008 whereas the slope decreased. The latter suggests a decreasing income elasticity of internet use over time but may also reflect the S shaped diffusion process where the first difference of the growth rate of per capita internet use is positive for countries which are in the early phases of the diffusion process and where it is negative for countries which are in the later phases of the diffusion process. A linear regression on the first difference of the growth rate of per capita internet users on the log of per capita GDP shows a positive slope until 2002 and a negative slope afterwards and indicates indeed that the growth rate of internet users has declined in high income countries relative to the growth rate of internet users in low income countries. 6 Figures 1 and 2 show that the diffusion of internet follows the traditional S shaped diffusion curve and that there is a clear positive relation between internet users and per capita GDP. Before 2003 high income countries showed to have higher growth rates of per capita internet users than low income countries whereas that has been reversed in most recent years such that on average the absolute difference of per capita internet users between high income and low income countries has become smaller in most recent years. The relation between internet use and economic growth is less obvious as can be seen from Figure 3. Although a linear regression between GDP growth per capita and per capita internet use shows a positive and significant slope the graph clearly shows that such simple model is far from complete. 7 The main objective of this section is to investigate the impact of internet use on economic growth in a fully specified growth model. [Insert Figure 2 about here] [Insert Figure 3 about here] In a related analysis (Choi and Hoon Yi, 2009) use an empirical growth model in which they employ per capita internet use, investment as ratio to GDP, government expenditure as ratio to GDP and the level of inflation as explanatory variables. Using the same dataset as we do but covering a time span from 1991 to 2000 they find a highly 6 A regression of the first differences of the growth rate of per capita internet users on the log of per capita GDP indeed shows a positive and significant slope in 1994, 1995, 1996, 1997, 1998 and in 2002 and a negative and significant slope in 2003 and 2005 (and non significant in the other years between 1992 and 2008). 7 Regressing the growth rate of per capita GDP on per capita internet use shows a slope of 0.015 with an standard error of 0.005 (p<1%). 10

positive and significant effect of internet use on economic growth. Using the same time period and using the same variables the results of (Choi and Hoon Yi, 2009) can be reproduced fairly well. Table 2, model (a) resembles their OLS results but now using the extended time span and adding lagged per capita GDP, openness and schooling enrolment as additional variables. 8 The investment ratio has a positive and significant impact on economic growth and both inflation and government expenditure ratio are significant and have a negative impact, all as expected. Lagged per capita GDP is significant and negative suggesting that countries with lower initial per capita GDP grow faster such that on average there is convergence. Secondary school enrolment rates and openness to international trade are also positive and significant. 9 Per capita internet use is significant and positive as also reported by (Choi and Hoon Yi, 2009). So from model (a) in Table 2 one would learn that internet use has a significant and positive contribution to economic growth additional to the impact of other variables that are included. Including time dummies to capture global movements in economic growth and thus to control for longitudinal variation dramatically changes the picture of the relation between per capita internet use and economic growth and the coefficient on per capita internet use becomes insignificant whereas the order of magnitude and the significance of all other explanatory variables remain unchanged (see model b in Table 2). A Wald test on joint significance of time dummies clearly rejects the null that the coefficients are jointly equal to zero (last row in Table 2). From Table 1 the within standard deviation of per capita internet use is slightly higher than the between standard deviation although the difference between these standard deviations is not very substantial implying that the longitudinal variation is comparable in size with the cross section variation. Compared to internet use the figures on inflation show a more considerable difference where the within standard deviation is much larger than the between standard deviation. Nonetheless this difference the coefficient on inflation remains stable when introducing time dummies whereas the coefficient of internet use becomes highly insignificant when comparing models (a) and (b). 8 Next to the variable indicated here also life expectancy at birth, fertility rate and some institutional factors such as corruption index and rules of law were initially included but did not give significant results. 9 To check for multicollinearity problems initially all independent variables are regressed on all (remaining) independent variables in a fixed effects model and no adjusted r squared proved to exceed 0.9. 11

The panel structure of the dataset allows for random and fixed effects estimation and the Sargan Hansen test as well as the Hausman test show that the fixed effects model has to be preferred. In models (c) to (e) the random effects variant of the panel model is firmly rejected indicating that the disturbance terms are correlated with country effects. 10 Model (c) is comparable to (Choi and Hoon Yi, 2009) but includes the same additional explanatory variables as before but also here excludes time dummies. Even in this case the coefficient of per capita internet use of the growth rate of per capita GDP becomes insignificant. So a fixed effects model that captures country specific effects by country dummies but without using time dummies cannot reject the hypothesis that internet use does not impact economic growth. This again contradicts the findings of (Choi and Hoon Yi, 2009). Model (d) includes time dummies which are jointly significant different from zero. The fixed effect estimate in (c) and (d) suggest a larger negative value of the lagged per capita GDP, so indicating a stronger convergence, and also the effect of trade on GDP growth is increased and highly significant whereas the effect of education has become insignificant different from zero if time dummies are included in model (d). As before the per capita internet variable remains insignificant. Both models show some autocorrelation as reported in the last but one row of Table 2. 11 [Insert Table 2 about here] Extending the analysis by allowing for two year lagged per capita GDP to capture higher order dynamic effects does not change these conclusions as reported by model (e). The long run coefficient of lagged per capita GDP remains negative, significant, and of the same order of magnitude. Also all other independent variables remain significant and of the same order of magnitude. Per capita internet use remains insignificant suggesting 10 The robust test on overidentifying restrictions as proposed by (Wooldridge, 2002) p 190 191 is displayed as Sargan Hansen Chi squared statistics including the corresponding p value and shows that fixed effects are never redundant and is to be preferred over the random effects model. In all cases the standard Hausman tests on non robust estimates of the equivalent models maintain the same conclusions (not shown in tables). 11 Autocorrelation is computed using the test for serial correlation in panel data as described by (Wooldridge, 2002) and (Drukker, 2003). 12