Fusion Cuisine for RAG: Z‑Scores, Rankers, and the Two‑Source Diet
A RAG system usually fails in one of two annoyingly familiar ways. It retrieves documents that are factually relevant but gives the model no clue about the task’s decision boundary. Or it retrieves labelled examples that show the decision pattern but are too parochial to help when the topic drifts. One source knows the world. The other knows the exam rubric. Naturally, many systems pick one and then pretend the compromise was strategy. ...