Information systems

The problem of state estimation has come to be known as data assimilation in many geophysical applications. I will review data assimilation for the atmosphere, especially for numerical weather prediction. A distinguishing characteristic of atmospheric data assimilation is the diversity and extremely large numbers of observations considered and the extremely large dimension of the state vector.

The role of recommender systems as a fundamental utility for electronic commerce and information access is well established with many commercially-available recommender systems providing benefits to both users and businesses. But, recommender systems tend to use simplistic user models that are additive in nature: new user preferences are simply added to the existing profiles.