Dear Economist,
As a keen silver surfer, I find YouTube an excellent way to revisit comedy favourites such as Monty Python and Peter Cook and Dudley Moore. I feel guilty watching pirated material, but what really puzzles me is why people post this material for my delectation. Can you explain?
O. Grizos

Dear O. Grizos,

It is a conundrum, I agree. Someone in possession of a vintage piece of sophisticated comedy – say, Derek and Clive Get the Horn – could simply spend his time watching it rather than posting it to the internet. The self-interested rational agent that populates some economic models would not behave like this.

The puzzle deepens when you consider the impressive achievements of the voluntary networks that have been enabled by the internet. Blogs are competing with online newspapers. Music-sharing networks have the record industry in a panic. Wikipedia needs no hype from me.

But while this behaviour may be economically and socially significant, most people participate only in the way you do – as consumers. J.K. Rowling’s books attract thousands of reviews on Amazon.com. Yet the overwhelming majority of her readers – more than 999 in every thousand – don’t bother to post a review. Frankly, if 0.1 per cent of people make unrewarded contributions to the internet, that’s just a rounding error away from nobody at all.

Economists love efficiency, and it is not very efficient to produce an explanation of behaviour that hardly anyone engages in. I suggest, then, that you do the research yourself. Film your conclusions and we’ll all watch them on YouTube.

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