"Hi Dan, I find all this information incredibly helpful and I loved your book. However I would love to see some controlled experiments to test your data for causation vs correlation. I would also be interested to see if the results are the same for all users depending on their number of followers. In other words, are the results the same for someone with 500 followers as someone with 30,000 followers? Keep up the great work." - Alistair (alpinefolk)