Researchers tracked 1,000 couples who were either married or in serious relationships over the course of five years, and then looked at patterns amongst those who were still together after five years. What they found is that the man should be at least five years older than the woman and the woman should have more education than the man for the best chances of the marriage standing the test of time.

This of course did not prove true in the case when either one or both partners had been divorced previously, and the scientists added that using "objective factors" such as age, education, and cultural origin "may help reduce divorce". If one partner had been divorced in the past, it lessens the chances of the relationship surviving. Interestingly though, if both partners had been divorced previously, while their chances of surviving are still not as good as those who had never divorced, the chances of survival are slightly better than those in a relationship where just one partner had been divorced.

One example of a celebrity relationship that according to this study is likely to last is that between Beyonce Knowles, 28, and her husband, Jay-Z, 39. She's younger, and also more educated. Jay-Z did not even receive a high school diploma.

The relationship between Michael Douglas, 65, and Catherine Zeta-Jones, 40, is an example of a relationship in which his previous divorce would count against them and lessen their chances of survival.