Catalogue cross-matching and Sherlock

A talk given at a Lasair-LSST User Review meeting, Oxford, September 13th 2023.

Sherlock is a boosted decision tree algorithm that mines a library of historical and on-going astronomical survey data in an attempt to predict the nature of the object based on the resulting crossmatched associations found. Here we describe Sherlock's integral role in Lasair, the UK's transient alert stream broker for Rubin Observatory's Legacy Survey of Space and Time (LSST).