Svd, Dimensionality Reduction, Latent Semantic Indexing, Machine Learning, Similarity Search.
Solution: Represent document using a more semantically accurate way, i.e., in terms of “concepts”. LSI (Latent Semantic Indexing) achieves this by analyzing the whole term-document matrix W, and by projecting it in a lower-dimensional “latent” space spanned by relevant “concepts”. More precisely,