effective vs effectivity

effective is not a noun while effectivity is a noun.

Word	Noun	Adjective	Verb	Adverb
effective	No	Yes	No	No
effectivity	Yes	No	No	No

effective (noun)	effectivity (noun)
	power to be effective; the quality of being able to bring about an effect

effective (adjective)	effectivity (adjective)
producing or capable of producing an intended result or having a striking effect
existing in fact; not theoretical; real
able to accomplish a purpose; functioning effectively
works well as a means or remedy
ready for service
exerting force or influence