Is your agency data-driven or more emotion- and hunch-driven? In today's economy, you'll want to be able to prove your social media campaigns work by looking at social media ROI. But how? During a recent Agency Summit, Christopher Penn gave an insightful talk about how agencies can deliver reports to their clients and tangibly demonstrate the value of their social media marketing activity. Christopher Penn is an authority on analytics, digital marketing, and marketing technology. On top of being a top 100 digital marketer, successful entrepreneur, best-selling author of over two dozen marketing books, and a prolific keynote speaker, he's