> I'm sorry, but in economics (or any other field that at least tries to
> be scientific), just because something has been done "many times"
> doesn't mean that we should do it. Just because many economists often
> assume that markets are perfectly competitive doesn't mean that we
> should do it. As my Mom used to say, if everyone else is jumping off a
> cliff, does that mean you should do it?
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I feel lazy today - the sun finally came after 5 days of rain, cold,
and wind; now I just wanna get high - so I will respond to this,
which only requires repetition (and incidentally, I repeat, agreement
with your basic point): such a measurement could be misleading if
we conclude that higher land yields imply a more efficient system.
Duby mentions an appropriate case re two wheat fields, showing
us that even when we are dealing with same grain "....the yields
were extremely variable, depending on the quality of the soil (the
wheat yields of two quite close Cluniac estates were in the ratio
6:1 and 2:1 respectively..., and on the climate..." (Fontana
Economic History).
