Lean-back and lean-forward online behaviors: The role of emotions in passive versus proactive information diffusion of social media content.

One of the main drivers of social media's influence is the easy way of generating information cascades via forwarding messages. Two basic modes of reposting information consist in sharing it without changes (lean-back) or adding or modifying content on top of the original message (lean-forward). In this work, we study those two modes of online information sharing. Using data from six cases extracted from Twitter, where retweets make up most of the content, we analyzed emotions in passive versus proactive information diffusion. Our findings show that emotional valence itself does not indicate significant differences between lean behaviors, while the activation of emotions like anger, disgust, fear, sadness, and joy is more informative. For example, disgust is more intense in lean-back and anger in lean-forward behavior. We also find that in proactive lean-forward communication, disgust and joy synchronize with the emotions of lean-back messages. A causal analysis of lean-forward information sharing reveals that disgust provokes a consistent increment of itself while it also decreases the appearance of anger in political topics. We discuss the implications of our findings for the study of emotions in active versus passive forwarding of information in social media.