WASHINGTON — Katie Xiao emigrated from China when she was 4 and always thought of herself as Americanized — until she started dating.

Subtle cultural clashes with Caucasian or Latino boyfriends led to unhappy breakups. It made her realize she's more Chinese than she thought. Now she wants to meet a man of Asian descent.

She recently went to a chocolate tasting and a cocktail mixer, both catering to Asian-Americans and immigrants. She spent Valentine's Day weekend making contacts at a Harvard Business School conference called "Asia in a Whole New World."

Sociologists and demographers are just beginning to study how the children of immigrants who have flowed into the country in recent years will date and marry. The generation that is coming of age is the most open-minded in history and living in the Obama era — where hues mingle in classrooms, nightclubs and the White House. Conventional wisdom has it that they will begin choosing spouses of other ethnicities as the number of interracial marriages rises.

But scholars delving into the U.S. Census have found a surprising converse trend. Although interracial marriages overall have increased, the rate of Hispanics and Asians marrying partners of other races declined in the past two decades. This suggests that the growing number of immigrants is having a profound effect on coupling, they say.

The number of native- and foreign-born people marrying outside their race fell from 27 to 20 percent for Hispanics and 42 to 33 percent for Asians from 1990 to 2000, according to Ohio State University sociologist Zhenchao Qian, who co-authored a study on the subject. The downward trend continued through last year, Qian said.

"The immigrant population fundamentally changes the pool of potential partners for Asians and Hispanics. It expands the number and reinforces the culture, which means the second generation ... is more likely to marry people of their own ethnicity," said Daniel Lichter, a sociologist at Cornell University.

Increasingly, singles are turning to a growing number of niche dating sites on the Internet, such as Shaadi.com and Persian singles.com. The large social networking groups Professionals in the City has expanded its repertoire over the past year to include "speed dating" nights for people of Asian, Latino or South Asian descent. Its president, Michael Karlan, noted that the Washington area has more than 1 million immigrants.

The 20- and 30-somethings drawn to these events say they have a deep yearning to connect with someone who shares their roots, yet they are conflicted about it.

"People grow up the entire time rebelling to our parents, doing everything we could to fit in and spending the majority of our time running away from the traditions and our heritage," said Bhavna Pandit, a political consultant of Indian descent. "Now I'm 29 years old, and I actually care about this stuff." She says Indian men in particular are in short supply in her Capitol Hill circles.

Researchers spent a decade following 3,300 children of immigrants in the New York region as they navigated adulthood, which led to a study published last year called "Inheriting the City: The Children of Immigrants Come of Age." They followed both the "second generation" children born in the United States and the "1.5 generation" — children of immigrants who came as youngsters — who were Dominican, Chinese, Russian Jews, South Americans and West Indians.

Researchers found that their subjects were constantly struggling with the desire to be open to people of all backgrounds vs. family expectations, and their own desires to sustain their culture. Most paired with others who shared similar racial or language backgrounds.

Many have tradition-minded parents who pressure them to marry soon after college graduation.

"They make little comments, like, 'Have I found anyone?' and 'We just met our friends who have grandchildren,' " said Rich Park, 33, a Korean-American in suburban Annandale, Va. "I want someone who understands what my life story is."

Their forebears often met spouses through family introductions or arranged marriages. Now families are spread over the globe, and modern love seekers don't want a mate whom their parents found in a note tacked on their temple's events board.

The researchers behind "Inheriting the City" found their subjects to be far more open-minded than their parents, whose views could be affected by racial or cultural bias in their home countries.

On a recent night in a dimly lit bar in suburban Arlington, Va., Park and Xiao were among about 30 singles gathered as Karlan moved through at four-minute intervals, telling the men when to switch seats. Participants took notes on their prospective dates; they would learn later through an anonymous e-mail system whether they had a match.

One whom Xiao met recently stands out: a Korean-American lawyer about her age. She is starting to feel "kind of nurturing" toward him.

She likes the self-deprecating way he writes his e-mails. ("You'll probably find this really boring but ... " he sometimes writes, prefacing a brainy thought. )

That's very Asian, she thinks. It feels like home.