- the relationship between physical capital and knowledge-related capital (broadband penetration and education); and
- the relationship between GDP per capita and the above
First, broadly, the findings of the study itself: "We estimate the effect of broadband infrastructure, which enables high-speed internet, on economic growth in the panel of OECD countries in 1996-2007. Our instrumental-variable model ... [shows] voice-telephony and cable-TV networks predict maximum broadband penetration. We find that a 10 percentage-point increase in broadband penetration raises annual per-capita growth by 0.9-1.5 percentage points. ...We verify that our instruments predict broadband penetration but not diffusion of contemporaneous technologies like mobile telephony and computers."
Interesting - a 10% increase in broadband penetration ups the growth rate by 0.9-1.5%. In other words, to get a 10% increase in GDP per capita out of a 10% rise in broadband penetration requires 6.4-10.7 years. Not a bad return. The problem here is that, of course, the starting levels from which this effect is measured are low, so the law of diminishing marginal returns has to kick in somewhere.
I took their data and run through some of it in a very crude way to see if I can glimpse other interesting aspects. Here are the results.
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Next, take a look at scatter plot relating GDP per capita to two measures of communications sector performance: broadband penetration for 2008 (the end score, if you want) and starting point measure (voice telephony penetration back in 1996).
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A very revealing chart next:
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Note Ireland. It is relatively poor in physical capital per GDP and yet relatively rich in GDP per capita. Why? Because we do have a modern economy - an economy where value is added through human capital side (of course this happens much more on the side of MNCs, where transfer pricing is used to import, artificially, human capital-intensive value-added, but it also happens in services economy, in our IFSC, etc). And yet, our education measure is far from being impressive.
The gap between our unimpressive levels of education and the levels of education consistent with the 'average' OECD pattern of relationship between education and GDP per capita, to me, clearly shows the importance of transfer pricing in our GDP figures. This gap is captured here by, in effect, showing that our capital and human capital stocks cannot support our GDP fully!
Here is more detailed view of our physical capital stock relative to our education (human capital stock).
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So here is a question no one is asking - is there such a thing too much of education? Is there an inverted U-curve for the relationship between education and income, whereby too smart for its onw good society leads to suboptimal levels of growth? After all, since the 1990s we are seeing an emerging trend in the developed world whereby the new generations of slackers are increasingly composed of highly educated people...
This is not an argument out of the blue - take example of a potentially 'too livable city' concepts discussed in a brilliant article here. Can the same happen to the 'too-knowledgeable-economy'?
Ok, couple more charts on the same point. Broadband penetration is positively correlated with capital formation... Hmmm. This might reflect the fact that higher stock of capital imply better infrastructure through which broadband can be delivered. The relationship is not very strong, though.
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Far from being dead, the age of Friedmans' Freedom to Choose is only dawning!
And the final point: education and broadband infrastructure are much more strongly (almost 4:1) positively correlated with each other than they are with physical capital.
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If they don't, the risk is they will end up being physical capital giants - countries where the world does its 'dirty work' of mass manufacturing widgets...