Can anyone help with a psychology term, barnim effect? Any ideas?

Answer 1

I believe you are are actually looking for it spelled like this: Barnum Effect.

Barnum Effect : is a term that is used in psychology. It is the tendency for people to accept very general or vague characterizations of themselves and take them to be accurate. A good example of this can be seen when people believe what is said about them in psychometric tests, personality profiles, astrological predictions, and so on.

Answer 2

Named after P.T. Barnum, the Barnum Effect is based upon his famous saying "There's a sucker born every minute." It has to do with being gullible.