Soundex is a useful option for reducing the search space (the blocking stage, with aims to have a high recall). TF-IDF is a useful option as part of a high pre

Soundex is a useful option for reducing the search space (the blocking stage, with aims to have a high recall). TF-IDF is a useful option as part of a high precision pipeline _post_ blocking. A two step pipeline is typical and necessary because the high precision pipeline, while more accurate than the blocking algorithm, suffers from being slow.