Rich girl meets poor boy (or vice versa). They fall in love and despite their differences, marry and live happily ever after.
It's the well-worn narrative behind countless sentimental Hollywood favorites (see: The Notebook, Cinderella, and Pretty Woman).
And now, just in time for Valentine's Day, new research is throwing cold water all over it.
"We tend to think in America that society is very fluid," said Kerwin Kofi Charles, an economist at the University of Chicago. "We like to think a Kennedy will marry some poor girl or boy. Well, no, no. Slow down with that."
Though rags to riches love stories are technically possible, economic analysis suggests they are extremely rare. In fact, the wealthier or poorer a person's parents are, the greater the chances that he or she will marry someone from the same financial background, according to a new study co-authored by Prof. Charles, Erik Hurst of the University of Chicago and Alexandra Killewald of the University of Michigan.
The study -- the first to look at whether parental wealth plays a role in marital patterns -- analyzed 1,820 married couples in the United States. The researchers sorted the spouses into five categories according to their parents' wealth.
Their findings are decidedly unromantic.
If money were irrelevant to spousal selection, wealthy people would be as likely to marry someone from the poorest category as from the richest, said Prof. Charles. One fifth of the wealthiest individuals would choose spouses from the poorest category, another fifth from the second poorest category and so on.
Instead, the study found that 40 per cent of men and women with parents in the wealthiest category married partners from the same financial background.
How many men reached across the financial divide to marry women from the poorest group? Just 10 per cent.
What about the rich girls? Even fewer wealthy women -- 8 per cent -- married men with parents in the lowest wealth category. Those that did stray out of their wealth category didn't go far: about 65 per cent of men and women with rich parents chose spouses from the same category or the one just below it.
The outcome was the same at the opposite end of the spectrum, with men and women in the poorest group most often finding partners from the same financial category. And the results didn't change much when the researchers adjusted for education and race - two elements thought to have a strong impact on marital patterns.
Interestingly, wealth affected the success of marriages as well. The richer a woman's parents were, the more likely her marriage was to fail, irrespective of how wealthy her husband's family is.
As for why money - or at least family money - matters, the authors have a couple of ideas. The most obvious is that people are more likely to interact with others from a similar financial setting. Wealth impacts where people live, what schools they attend and therefore whom they meet. The traits people are most attracted to may also be more prevalent in those from the same financial background.
Point is, marrying outside your wealth bracket in the U.S. is "unlikely if you are poor and rare if you are rich," said prof. Charles.
Of course, it is the rare (but still possible) nature of the poor boy marries rich girl trope that makes it such great cinematic fodder.
"It's not impossible, true," said prof. Charles. "But don't hold your breath"
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