this is completely specified it's not just a framework and it you know every year tens of frameworks are developed with just have skeletons and then pieces are missing and usually this missing pieces you know turn out to be really really difficult and so this is completely and uniquely defined and we can analyze that mathematically and we've also developed some approximations I can talk about it a little bit later that would dissolve the top-down approach like say for Normans minimax theory that's the theoretical optimal