> Third, book recommendation systems based on your reading history can be helpful, but only so much. Book recommendation systems should be a hybrid system with

> Third, book recommendation systems based on your reading history can be helpful, but only so much. Book recommendation systems should be a hybrid system with content-based filtering and collaborative filtering systems. Reading history (lagging indicator) + browsing history (leading indicator) would form the basis of a content-based filtering. The collaborative filtering part would ensure the system compares users with same reading patterns. A system like this should address all author's concerns.