"It's about family," she said. "The parents have an optimistic view of bringing up their children in the United States. One important motivation for immigrants is to improve their children's lives. The United States is the land of opportunity. If we work hard, we will get it."
New immigrants tend to settle in communities that have many other residents from the same part of the world, thus buttressing the "cultural tools" that might otherwise diminish over time.
"If you go to Chinatown you see bankers there, but you also see people washing dishes. There's many different people there. So even if your parents aren't highly educated, you have other role models in your community," Hao said.
That further supports the idea that success comes to those who work the hardest, the study notes.
But why does it end with the third generation? Hao speculates that the cultural tools from the old country will have been lost by then.
The new kids "didn't have to make sacrifices to come here," she said. "They don't have high motivation to change their family's position in society." In other words, they can get along while doing less.
There's one surprise in the study. Hao had hypothesized that some of the children would suffer from depression because of the intense pressure to succeed, but the findings do not support that. Even if they don't measure up to their parent's expectations, she speculated, they are doing better than their peers, so they probably feel pretty good about themselves.
Of course, none of this means every kid who arrives here from somewhere else is going to outperform every kid in the neighborhood.
"Not all of them, but more of them," will likely succeed, she said.