PATTY TOLAN is the first (and, to date, only) recruit to be hired by the ANSWER THE CALL GHOSTBUSTERS. She's potentially the bravest of the team, being the one who most consistently recognizes the danger that they put themselves in by dealing with the supernatural.
Patty was formerly employed by the MTA, a job she enjoyed because it gave her a lot of time for books -- she is more well-read than her colleagues in the Ghostbusters (which would probably embarrass at least Abby and Erin if Patty ever brought it up).
She enjoys Ghostbusting -- researching ghost origins and motives finally gives her an outlet to use her education.