Re: Economic Growth Assuming Machine Intelligence

Robin Hanson (
Wed, 07 Oct 1998 08:52:51 -0700

J. Maxwell Legg writes:
>>>It is easier to get more variation in growth rates with endogenous
>>>growth models, and there is also less consensus on how to model
>>>endogenous growth. So to avoid the accusation that I cooked my big
>>>growth speedup implications, I choose to use exogenous growth.
>>>This may provide a conservative estimate of growth implications. ...
>>That seems like a good reason to use exogenous growth. ...
>I'd say that having less consensus on how to model endogenous growth may
>mean there are more endogenous systems to choose to model from and large
>numbers of actual adequate trials to take place instead of supression of
>large numbers of models. Wouldn't a wider field be a better base to choose
>from than continuing with the restricted exogenous growth model. More
>challenging may be to allow the fittest model to continue to grow and in
>reality cease to be a model and proving something or the other.

I'm not sure I follow you. We're talking about what best models the world economy as a whole, not about models of competing entities where the fastest growing one will win out over the others. My choice of exogenous growth models is to provide more of a lower bound on growth rates, not to give the closest model to reality. In modeling, more realism comes at the expense of more complexity, and complexity makes it harder to compare and evaluate models. So one often prefers to examine simpler models.

Robin Hanson RWJF Health Policy Scholar, Sch. of Public Health 510-643-1884 140 Warren Hall, UC Berkeley, CA 94720-7360 FAX: 510-643-8614