With increasing numbers of people in Japan getting married late or not at all, local governments are turning to a new weapon in their fight to reverse the trend -- artificial intelligence.

Authorities in many regions have been organizing traditional "konkatsu" matchmaking events with AI sifting compatibilities between potential partners. They say it has sometimes led to people who would never have imagined being together tying the knot.

Even the central government is now putting its support behind such moves as depopulation progresses throughout the country. Subsidies for publicly run AI matchmaking events have been expanding since fiscal 2021.

According to the Children and Families Agency, 31 of Japan's 47 prefectures offered AI matchmaking services for finding marriage partners as of the end of March last year, with the Tokyo Metropolitan Government joining them in December.

Screenshot shows the homepage of the online marriage support center established by Shiga Prefecture in western Japan. (Kyodo)

Worried about its declining birthrate and aging population, Ehime Prefecture in western Japan has been using big data to match people with potential partners.

The prefecture's system recommends partners based on personal information registered with the marriage support center and the internet browsing history of the person looking for a mate.

"The purpose of this program is to broaden people's horizons so they are not limited to thinking only about what academic institutions people went to or their age," Hirotake Iwamaru, a counselor at the center, said. Around 90 couples are married each year with the center's support.

Tochigi Prefecture, north of Tokyo, utilizes the same system. Katsuji Katayanagi of its marriage support center said, "Young people tend to leave things to others to do, so I think we need, occasionally, to ask big data to recommend partners."

In another system, users answer more than 100 questions, based on which AI analyzes the qualities a person is looking for in a potential partner and vice versa before introducing them.

In Saitama Prefecture, near Tokyo, where the system was introduced in 2018, 139 couples were married by the end of November last year. Some admit to meeting a person they might not have chosen on their own, with a prefectural official saying the system is "providing for a variety of encounters."

Shiga Prefecture launched an online marriage support center in 2022, triggered by the coronavirus pandemic, and uses a system similar to the one adopted by Saitama. As of the end of January, 13 couples had decided to get married via the support center. Six of them were with partners introduced by AI.

A woman in her 30s who is set to marry a partner she met through an AI service, said, "I had some resistance and anxiety about using the system at first, but I am glad I had the courage to register."

Mayu Komori, chief administrator of the Shiga prefectural child and youth bureau, suggested that those who sign up for the service are serious about getting married, noting the not-so-cheap registration fee of 15,000 yen ($100) for two years.

"Many people also feel reassured because it's run by the prefectural government," Komori added.

Takeaki Uno, a professor of algorithm theory at the National Institute of Informatics who was involved in developing Ehime Prefecture's system, said the use of AI in matchmaking services broadens the range of potential partners.

"In terms of cost-effectiveness, it is easier to use than the private sector, and it offers advantages to many people," he said.

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