Modern search engines has to keep up with the enormous growth in the number of documents and queries submitted by users. One of the problem to deal with is finding the best k relevant documents for a given query. This operation has to be fast and this is possible only by using specialised technologies.
Block max wand is one of the best known algorithm for solving this problem without any effectiveness degradation of its ranking.
After a brief introduction, in this talk I’m going to show a strategy introduced in “Faster BlockMax WAND with Variable-sized Blocks” (SIGIR 2017), that applied to BlockMaxWand data has made possible to speed up the algorithm execution by almost 2x.
Then, will be presented another optimisation of the BlockMaxWand algorithm (“Faster BlockMax WAND with Longer Skipping”, ECIR 2019) for reducing the time execution of short queries.