Before revision:  the top-level is described by shared risk factors, the next level combines shared risk factors with information variables and bottom-up agent generated structurebased on the framework of arbitrage pricing theory, the lowest level is that of agents generating the prices of individual traded assets and a mechanism for emergence or innovation is considered . Concepts in the hierarchy of complexity are interrogated via five causation classes and the concept of actors, who serve as exemplars for types of causation, is reviewed .
After revision:  the lowest level is occupied by agents generating the prices of individual traded assets; the next level entails aggregation of stocks into markets; the third level combines shared risk factors with information variables and bottom-up agent generated structurebased on the framework of arbitrage pricing theory, the lowest level is that of agents generating the prices of individual traded assets and a mechanism for emergence or innovation is considered . Concepts in the hierarchy of complexity are interrogated via five causation classes and the concept of actors, who serve as exemplars for types of causation, is reviewed .