Problem: Take the characteristics you identified as potential features of an operational definition for "smiling" and share them here. Discuss the relative merits of the features you selected and debate the features your colleagues have come up with in their own forum posts. On Friday, I will list the key features that folks have come up with in a survey that you can use to vote for the features we should collectively use to operationally define a "smile". We'll use this consensus definition for the next step of our smile exercise.