OkCupid Experimented on Users, Then Blogged About It

— -- In the wake of Facebook's recent admission of toying with users' emotions, another site revealed today that it, too, likes to "experiment on human beings" -- and lie to them.

OkCupid founder Christian Rudder published a blog on Monday detailing three recent experiments the online dating site performed that manipulated users' perceptions, including telling a "small sample" of couples that they were highly compatible when they actually were not.

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"The ultimate question at OkCupid is, does this thing even work?" wrote Rudder, referring to its algorithm for accurately calculating match percentage. "In the back of our minds, there’s always been the possibility: maybe it works just because we tell people it does. Maybe people just like each other because they think they’re supposed to?"

To test the theory, Rudder and colleagues "took pairs of bad matches (actual 30 percent match) and told them they were exceptionally good for each other (displaying a 90 percent match.)" As hypothesized, the couples initiated contact with one another because they believed what the site told them.

But it didn't end there. The experiment also determined that users were more inclined to actually like each other when told to, exchanging four or more messages, even if they wouldn't normally.

"The four-message threshold is our internal measure for a real conversation," wrote Rudder. "And though the data is noisier, this same 'higher display means more success' pattern seems to hold when you look at contact information exchanges, too."

Rudder did not immediately respond to ABC News' request for comment on the size of the sample tested, how long the experiment lasted and whether any couples notified of it had reacted positively or negatively.

But readers were quick to respond to the blog post, comparing it to Facebook and drawing their own conclusions.

"Facebook secretly manipulated the users of the site, attempting to alter their emotions ... quite possibly at the behest of creepy interests sponsoring this experiment," commented one user identified as SteveRestless. "All I can see here is honest curiosity and a desire to improve the site."

Others were not as forgiving.

"I hope you didn’t cause me to miss out on a relationship while playing around with the data," wrote another. "It is hard enough for me as it is. Also, people trusting your match percent is what you want, so don’t lie to them about it."