Guest post by Dan Zarrella, author of Zarrella’s Hierarchy of Contagiousness The key to applying science to marketing is being prescriptive. Calculating and analyzing data that is interesting is fun, but information becomes useful when it tells you how to achieve a specific goal. Throughout my career, one of the goals I’ve focused on is the engineering contagious ideas. I’ve worked for years, using science and data to understand how to craft content that spreads like wildfire. Humans have been…