Asked about Retrieve broadly, then rank precisely
What is a cross-encoder and why not use it for everything?
An answer that works
It reads query and candidate together and scores the pair, which is much more accurate than comparing independently computed vectors. It also means one forward pass per candidate, so it is far too slow to run over a whole corpus.
Reading an answer is not being able to give one. The section that teaches this is Retrieve broadly, then rank precisely, 6 hours of Reranking & hybrid search.
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