CFAI text, book 1, pg 613, says the following: an increase in TFP does not affect the relative productivity of the inputs.
Schweser says the following: Technological progress enhances the productivity of both labor and capital.
Why are these 2 saying different things?
They’re not; at least, they’re not necessarily.
Schweser’s saying that technology can enhance labor’s productivity and capital’s productivity by, say, 10% each.
CFA Institute’s saying that if they both increase by 10% their relative productivity (i.e., relative to each other) hasn’t changed: if capital’s productivity were twice labor’s productivity before the addition of technology (an increase in TFP), it’ll still be twice labor’s productivity after the addition of technology.
The reason I say “not necessarily” is that Schweser’s statement, in isolation, allows that technology could enhance labor’s productivity by a different percentage than its enhancement of capital’s productivity. CFA Institute’s statement says that the enhancements will be the same (as a percentage).