Here’s an interesting statistical breakdown of “match percentages” through OKCupid, an online dating service, based on indicated religious affiliation and level of seriousness.
It’s worth a read for no reason other than that it’s kind of interesting. There are a few other factors considered throughout the piece too.
“All OkCupid users create their own matching algorithms, so when we determine who matches who, we’re just crunching the numbers people give us. A match percentage between two people is a condensed, yet statistically valid, expression of how well they might get along.”
“In short, our method is this: we host an ever-changing database of user-submitted questions, covering every imaginable topic, from spirituality to dental hygiene. To build their own match algorithms, our users answer as many questions as they please (the average is about 230). When answering a question, a user also picks her how her ideal match would answer and how important the question is to her. It’s very simple, and it removes all subjectivity on our part. We simply crunch the numbers.”
Here’s a table. The average “match percentage” is 60.2%.