Don't depend on friends or family for a new job. One of the most influential theories in social science says that you are more likely to get a new position if you have weak ties with people. In 1973, Mark Granovetter wrote a paper that received more than 67,000 citations. The theory of the strength of weak ties was not proven to be true for decades. Forging weak ties can help people get new jobs, according to a study that looked at more than 20 million people on the professional social network site. It shows which types of connections are most important.

Dashun Wang, who was not involved in the new study, said the strength of weak ties is a cornerstone of social science. Granovetter interviewed people late in their career and asked them about their experiences with changing jobs. Many had assumed that new positions came from sources such as close personal friends who would put in a good word, headhunters who would seek out strong candidates or public advertisements. Granovetter's analysis shows that people get new jobs most frequently through friends of friends, even if they didn't know they were looking for a job. "That really shook people up because assumptions about how people find the best jobs in life doesn't look to be true - it looks like actually strangers might be the best contacts for you."