I'm a monster for putting out economic theory (10)
I believe the answer is:
Here is my best explanation:
'economic theory' is the definition.
'i'm a monster for putting out' is the subsidiary indication.
'for putting out' indicates anagramming the letters (out can mean wrong or inaccurate).
'imamonster' is an anagram of 'monetarism'.
(Another definition for monetarism that I've seen is "A way to regulate the economy".)