When rich people marry other rich people, social and financial inequality gets worse – here's how

Hamish McRae

The royal wedding was not really about economics, though if there were indeed upwards of two billion people watching at least some of it on television – getting towards one third of humankind – there will certainly be an economic impact. That will unfold in the months ahead. Meanwhile there is one aspect of the wedding that highlights a hugely important economic issue: the decline of random mating.

To explain, the issue is whether people marry, or form partnerships, with people who are like themselves in education, income and so on. Or do they choose people who are very different. If people choose those who are like themselves, that is called assortative mating. If they choose people who are different, that is random mating.

In the case of Duke and Duchess of Sussex, as they now are, it was pretty random. Meghan Markle was a successful actress, with a net worth of something like $5m (£3.5m), hugely impressive for someone in their mid-30s. But quite aside from being, as she described herself “a confident mixed race woman”, she is in many other ways very different from her new husband.

She is a brunette, he is ginger; she is petite, he is tall; their backgrounds and upbringings were of course vastly different. And while there has been a long tradition of grand Britons marrying energetic Americans – remember Winston Churchill had an American mother – the general pattern of recent years, particularly in the US, has been for mating to become less random. In other words, people are tending to choose mates who are more like themselves, not less. One result is increased inequality.

There have been a number of studies of this, of which the best-known (and much criticised) one was published by the National Bureau of Economic Research in the US, Marry Your Like: Assortative Mating and Income Inequality.

It suggested that this change in mating patterns accounted for much of the rise in inequality of income in the US between 1960 and 2005. Some reworking of the data gave a somewhat different gloss, in that it seems the rise of single households was much more to blame. But the bigger point here is that if well educated young people choose other well educated young people as their life partners, then their children are likely to have a better start in life. The more that the rich partner with the rich, the greater the entrenched advantages of their children and children’s children.

There is a further twist. This study of US data runs only up to 2005. Since then dating has been transformed by the explosive growth of dating apps. Tinder was founded in 2012. If people specify the sort of person they would like to meet, rather than bumping into them at the pub, so to speak, the random element in dating is further reduced. It seems that people tend to specify people of similar education, interests, and background. Actually, Prince Harry’s new bride appears to be totally different from all the other women he dated, and I hardly think he would have specified someone like her had he gone on Tinder.

So what’s to be done? Well, in a way, nothing. If rich kids want to choose other rich kids to set up families, so be it. All that societies can do is to focus on opening up lines of opportunity for everyone, and helping perhaps to nudge people away from behaviour that is likely bring them disadvantages in later life.

Insofar as inequality is the result of people making particular life choices, then it is very hard to lean against it. In Britain there does seem to have been some decline in income inequality in recent years, though thanks to a decade of very low interest rates and the resultant rise in asset prices, wealth inequality has widened. Maybe the message to governments is simply that they should strive not to make inequality worse.

Where I think there is a message for all of us is that there is a random element to all our societies that should be celebrated. We saw that in the wedding. These are two privileged young people, but they are privileged in different ways. UK royalty is pretty much top of the global pecking order. But the new Duchess was a long way up the Hollywood elite – and she did it herself by her own hard work.