# Learning to Rank
# Models
Point Wise vs Pair wise vs List Wise
# Click Models
Random Click Model: Every document has the same chance of being clicked.
Click Through Rate Model: Uses the fact that the dirst doc is clicked far more than the second document.
Cascade Model : a click in the third item also tells us something about the first two items. Only one click per session is assumed.
Dynamic Bayesian Network Model: Supports multiple clicks in a search session and the difference actual relevance of a document.
