A Social Strategy: How We Profit From Social Media

by Mikolaj Jan Piskorski,
Psychology Today, July 3, 2014

"I am always quite surprised how many people 'like' my Facebook posts with my runs or leave comments," a Nike Plus user told Mikolaj Piskorski, a professor at the Harvard Business School. "Perhaps the most unexpected part of all this is that a few of the people I know reached out to me and said they wanted to run together."