Implicit Personality Theory 

 Implicit personality theory, or IPA, deals with the predictions we make about an individual after learning certain personality traits they hold. For example upon meeting someone who is quiet, many assume that person must also be shy. Again upon meeting someone for the first time who is very happy, many might think they are also an extremely friendly individual.
These ideas held about individuals may or may not actually be true. Someone who is quiet might just be tired or in no mood to talk, while the happy person isn't always friendly, but is just having a very good day.