StackExchange uses a scarcity design pattern when new users are restricted in how many comments, up votes, and down votes they can post contingent on their score/rank. My client wants to implement similar gamification of scarcity pattern in which users get a weekly allowance of credits, and there's a fixed cost to post replies in a debate forum. This is intended to promote higher quality content, based on the idea that scarcity motivates more carefully considered responses.
I have expressed doubts to my client that this game mechanic will be successful at motivating the target behavior, which is higher quality content. I have suggested using a positive feedback mechanism to reward the target behavior, rather than using scarcity to discourage dis-preferred behavior.
I would like to understand the trade-offs in Gamification between motivating desired behavior through positive feedback (e.g. badges) versus discouraging dis-preffered behavior through negative feedback (e.g. scarcity pattern). I am interested in specific examples of success or failure of either mechanism as it relates to this question. (No I am not trying to start a discussion, thank you for your concern though.)
As an example of a precise testing of the above question, one could use the SE API to look at user behavior patterns before and after specific positive and negative feedback events. Since SE uses both types of game mechanics, we could look at how user behaviors may change after such events (assuming they're included in the SE API).