Most social networks have implemented extensive, complex privacy controls in order to battle the host of privacy concerns that initially plagued their online communities. These privacy controls have taken the form of access restriction, which allows users to specify who is and who is not allowed...

Price is the most visible signal produced by competition and interaction among a complex ecology of entities in a system called financial markets. This thesis deals with statistical analysis and model identification based on such signals. We approach this problem at various levels of...