UNITS A by UNITS B

[Jonathan Dushoff <dushoff@gate.sinica.edu.tw>]

> Dear listers,

> Every time I read pg/kg/d, or USD/g/mo, or similar indications, it
> disturbs me.

> Mathematics basics tells us that pg/kg/d = pg.d/kg.  So, in order to
> put things straight, what about indicating pg.kg-1.d-1?

I think that pg/kg/d is easy to read (picograms per kilogram per day)
and easy to understand.  I am not convinced it is mathematically wrong,
either, although I'll admit that it's mathematically awkward.  In fact,
I think it's mathematically correct (move from left to right, just as in
a - b - c).  I would find your suggestion very hard to read and
understand if I had not read your explanation, and I still think that it
is confusing and more difficult.

Jonathan Dushoff