From the UK Telegraph:

A decade ago, I set out to investigate luck. I wanted to examine the impact on people's lives of chance opportunities, lucky breaks and being in the right place at the right time. After many experiments, I believe that I now understand why some people are luckier than others and that it is possible to become luckier.

To launch my study, I placed advertisements in national newspapers and magazines, asking for people who felt consistently lucky or unlucky to contact me. Over the years, 400 extraordinary men and women volunteered for my research from all walks of life: the youngest is an 18-year-old student, the oldest an 84-year-old retired accountant.

Be lucky -- it's an easy skill to learn

On reading the article, the takeaway message seems to be that the 'unlucky' systematically fail to take advantage of high-expected-but-low-median value opportunities.