0 a person who is an expert in the part of economics that studies individual markets and businesses, or how individual people spend or earn money:
As a microeconomist, I study small economic units such as individual households.
That distinction no longer can be found in the choice of tools, since microeconomists and macroeconomists use most of the same tools.
I don't think any microeconomist would even ask questions about nonlinearity; to them it is just a matter of common sense.
