"However, upon a face-to-face meeting, most of this list goes out the window — people instead rely on their gut-level reaction to another person." The other problem, according to the research, is the emphasis placed on clients' similarities.

"To be sure, similarity on some dimensions, like race and religion, does predict relationship well-being," two of the study's co-authors wrote in The New York Times.

The incidents have been reported to Edmonton police and are being investigated.

Take the 2012 article Online Dating: A Critical Analysis From the Perspective of Psychological Science.

The study's authors sifted through decades of research about what makes people romantically compatible.

But can a formula determine whether two people will have a successful long-term relationship? According to market research company IBISWorld, the online dating industry made $153 million in Canada in 2014.

Services like e Harmony and promise to find you the best potential matches based on complex and tightly guarded algorithms.

According to a 2014 poll from the Pew Research Centre, "online violence is especially more pronounced at the intersection of gender and youth." The poll surveyed 2,849 Americans online.

It found that, of those surveyed, 26 per cent of women aged 18 to 24 reported they had been stalked online, and at least 25 per cent of the women said they had experienced online sexual harassment.

Within 24 hours, the first stranger appeared at the building's front door.

Her attempts to have the fake profiles removed from the dating website have been unsuccessful.

Plenty of Fish does have a strict anti-harassment policy, and multiple ways for users to report abusive or fraudulent profiles.

However, the company spokesperson declined to provide further comment on what processes are in place to prevent fake profiles, or what happens when complaints are flagged to police.

"It is very very difficult, if not impossible, to predict initial chemistry using variables assessed before two people meet each other," said study co-author Paul Eastwick, an assistant professor at the University of Texas at Austin.