I much prefer: (x/y)(dy/dx)
because it is more intuitively understandable, even to folks not well
versed in linear algebra but who may be interested in the results of
the research, or who might learn more about it in the future if they
think that it looks useful. This quantity clearly represents the
fractional change in y for a given fractional change in x. In words,
I typically describe it as "the % change in y for a 1% change in x,"
when giving talks to general audiences.
I have little intuitive "feel" for logarithms and, putting myself in
the position of one being presented with the relationship in logarithmic
form for the 1st time, I think I would have to convert it before
understanding it at a "gut" level."
-Paul
