^ Great answer. So far, this is the only correct one in the thread. I took Information Retrieval 101 in grad school and it was an interesting course. If you'

^ Great answer. So far, this is the only correct one in the thread. I took Information Retrieval 101 in grad school and it was an interesting course. If you're curious to learn more, term frequency–inverse document frequency (tf–idf) is a good place to start. The underlying idea is surprisingly simple. https://en.wikipedia.org/wiki/Tf–idf https://en.wikipedia.org/wiki/Tf–idf Likewise with the core of Google's (original) ranking algorithm, PageRank, which is inspired by ideas like h-index. https://en.wikipedia.org/wiki/PageRank https://en.wikipedia.org/wiki/PageRank Also, the "standard" book which we used is quite readable: Introduction to Information Retrieval by Manning, et al. https://www.amazon.com/Introduction-Information-Retrieval-Christopher-Manning/dp/0521865719/ https://www.amazon.com/Introduction-Information-Retrieval-Ch...