Algorithms, and not friends and family, are now the go-to matchmaker for people looking for love, Stanford sociologist Michael Rosenfeld has found.

In a new study published in the Proceedings of the National Academy of Sciences , Rosenfeld found that heterosexual couples are more likely to meet a romantic partner online than through personal contacts and connections. Since 1940, traditional ways of meeting partners – through family, in church and in the neighborhood – have all been in decline, Rosenfeld said.

Rosenfeld, a lead author on the research and a professor of sociology in the School of Humanities and Sciences , drew on a nationally representative 2017 survey of American adults and found that about 39 percent of heterosexual couples reported meeting their partner online, compared to 22 percent in 2009. Sonia Hausen, a graduate student in sociology, was a co-author of the paper and contributed to the research.

Rosenfeld has studied mating and dating as well as the internet’s effect on society for two decades.

Stanford News Service interviewed Rosenfeld about his research.

What’s the main takeaway from your research on online dating?

Meeting a significant other online has replaced meeting through friends. People trust the new dating technology more and more, and the stigma of meeting online seems to have worn off.

In 2009, when I last researched how people find their significant others, most people were still using a friend as an intermediary to meet their partners. Back then, if people used online websites, they still turned to friends for help setting up their profile page. Friends also helped screen potential romantic interests.

What were you surprised to find?

I was surprised at how much online dating has displaced the help of friends in meeting a romantic partner. Our previous thinking was that the role of friends in dating would never be displaced. But it seems like online dating is displacing it. That’s an important development in people’s relationship with technology.

What do you believe led to the shift in how people meet their significant other?

There are two core technological innovations that have each elevated online dating. The first innovation was the birth of the graphical World Wide Web around 1995. There had been a trickle of online dating in the old text-based bulletin board systems prior to 1995, but the graphical web put pictures and search at the forefront of the internet. Pictures and search appear to have added a lot to the internet dating experience. The second core innovation is the spectacular rise of the smart phone in the 2010s. The rise of the smart phone took internet dating off the desktop and put it in everyone’s pocket, all the time.

Also, the online dating systems have much larger pools of potential partners compared to the number of people your mother knows, or the number of people your best friend knows. Dating websites have enormous advantages of scale. Even if most of the people in the pool are not to your taste, a larger choice set makes it more likely you can find someone who suits you.

Does your finding indicate that people are increasingly less social?

No. I f we spend more time online, it does not mean we are less social.

When it comes to single people looking for romantic partners, the online dating technology is only a good thing, in my view. It seems to me that it’s a basic human need to find someone else to partner with and if technology is helping that, then it’s doing something useful.

The decline of meeting partners through family isn’t a sign that people don’t need their family anymore. It’s just a sign that romantic partnership is taking place later in life.

In addition, in our study we found that the success of a relationship did not depend on whether the people met online or not. Ultimately, it doesn’t matter how you met your significant other, the relationship takes a life of its own after the initial meeting.

What does your research reveal about the online world?

I think that internet dating is a modest positive addition to our world. It is generating interaction between people that we otherwise wouldn’t have.

People who have in the past had trouble finding a potential partner benefit the most from the broader choice set provided by the dating apps.

Internet dating has the potential to serve people who were ill-served by family, friends and work. One group of people who was ill-served was the LGBTQ+ community. So the rate of gay couples meeting online is much higher than for heterosexual couples.

You’ve studied dating for over two decades. Why did you decide to research online dating?

The landscape of dating is just one aspect of our lives that is being affected by technology. And I always had a natural interest in how new technology was overturning the way we build our relationships.

I was curious how couples meet and how has it changed over time. But no one has looked too deeply into that question, so I decided to research it myself.