how does hyperbolic growth explain two centuries of approximately constant GDP per capita growth trend in the US or in the UK?
It seems to me like this fact is often overstated or cherry-picked. E.g. Our world in data has UK GDP per capita at 2.3k pounds in 1800, 4.9k in 1900, and 24.4k in 2000. That’s more than twice as fast in the second century as the first. Moreover, from 1800-1900 the UK seems much more plausible to me than the US as a proposal for a frontier economy (rather than one benefiting from catchup growth and expansion into new territory).
Hyperbolic models are definitely surprised that acceleration here was more like 2x instead of 4x. There are obvious factors they ignore like low fertility that seem crucial to explaining that gap. But most of all they are surprised by the apparent slowdown in growth since 1960 instead of continued acceleration.
I don’t find the accusation particularly compelling unless you want to suggest an alternative model.
Broadly speaking I think that on hyperbolic models the “great stagnation” is definitely a real thing and it’s a lot of noise, and it generates a lot of ongoing surprise if you don’t include autocorrelations.
(Whereas on growth mode models this is the typical state of affairs punctuated by periodic transitions—unless you want to use something like Robin’s model, which is also surprised by the great stagnation rather than ongoing acceleration to 12%/year growth.)
It seems to me like this fact is often overstated or cherry-picked. E.g. Our world in data has UK GDP per capita at 2.3k pounds in 1800, 4.9k in 1900, and 24.4k in 2000. That’s more than twice as fast in the second century as the first. Moreover, from 1800-1900 the UK seems much more plausible to me than the US as a proposal for a frontier economy (rather than one benefiting from catchup growth and expansion into new territory).
Hyperbolic models are definitely surprised that acceleration here was more like 2x instead of 4x. There are obvious factors they ignore like low fertility that seem crucial to explaining that gap. But most of all they are surprised by the apparent slowdown in growth since 1960 instead of continued acceleration.
I don’t find the accusation particularly compelling unless you want to suggest an alternative model.
Broadly speaking I think that on hyperbolic models the “great stagnation” is definitely a real thing and it’s a lot of noise, and it generates a lot of ongoing surprise if you don’t include autocorrelations.
(Whereas on growth mode models this is the typical state of affairs punctuated by periodic transitions—unless you want to use something like Robin’s model, which is also surprised by the great stagnation rather than ongoing acceleration to 12%/year growth.)