With the advance of social network sites, employers can screen applicants'
online profiles to gain additional personal information without the
applicants' awareness. We investigate whether employers rely on such online
information when deciding to call an applicant back for interview. During a
12-month period, we set-up a field experiment and sent more than 800
applications of two fictitious applicants that differ for a signal - their
perceived origins - solely available on their Facebook profiles. A 40 \% gap
between the two applicants highlights that online profiles are used to
screen and select applicants. For many recruiters, Facebook profiles have
become a part of the application material. An unexpected change in the
Facebook layout altered the display of our online signal. This natural
experiment allows us to pinpoint the cause of screening, and therefore the
odds of being called back for interview, within the online profile.