postmessage_293339″> For many, a successful marriage can be put down to attraction, devotion, patience – and true love. But one group of statisticians begs to differ.
They have developed a distinctly unromantic formula to predict how compatible a couple are based on their ages, education and previous divorces.
The experts claim their theory can tell in advance that some couples are up to five times more likely to end up getting divorced than others.
According to the study, the couples with the best chance are those where a woman with a superior education marries a man who is five or more years older than herself.
Neither should be a divorcee.
By comparison, a marriage where a woman partners an equally poorly educated male divorcee who is five or more years her junior is up to five times more likely to fail.
The study is good news for David Cameron, 43, and wife Samantha, 38. Meanwhile, US President Barack Obama, 48, and wife Michelle, 45, may have only a three-year difference in age but have been married for 17 years.
But the study may not be welcomed by Michael Douglas, 65, and his 40-year-old wife Catherine Zeta-Jones – the research suggests a marriage is more likely to fail if only one partner has been previously divorced, and Douglas was married once before.
Academics including Dr Emmanuel Fragnière of the University of Bath studied interviews with 1,534 Swiss couples who were either married or in a serious relationship. Five years later they followed up 1,074 of the couples to see which had separated.
Using the data collected about their age, education, nationality and previous relationships, they found the factors that many of those who broke up had in common.
Psychologists then analysed the importance of each factor to build up profiles of an ideal marriage and a nightmare couple. With age, they found that if the wife is five or more years older than her husband, they are more than three times as likely to divorce than if they were the same age.
With education, couples in which neither partner has studied much are the most likely to break up. Those where both are well educated are half as likely to divorce.