Fast schemes for online record linkage

The process of integrating large volumes of data coming from disparate data sources, in order to detect records that refer to the same entities, has always been an important problem in both academia and industry. This problem becomes significantly more challenging when the integration involves a huge amount of records and needs to be conducted in a real-time fashion to address the requirements of critical applications. In this paper, we propose two novel schemes for online record linkage, which achieve very fast response times and high levels of recall and precision. Our proposed schemes embed the records into a Bloom filter space and employ the Hamming Locality-Sensitive Hashing technique for blocking. Each Bloom filter is hashed to a number of hash tables in order to amplify the probability of formulating similar Bloom filter pairs. The main theoretical premise behind our first scheme relies on the number of times a Bloom filter pair is formulated in the hash tables of the blocking mechanism. We prove that this number strongly depends on the distance of that Bloom filter pair. This correlation allows us to estimate in real-time the Hamming distances of Bloom filter pairs without performing the comparisons. The second scheme is progressive and achieves high recall, upfront during the linkage process, by continuously adjusting the sequence in which the hash tables are scanned, and also guarantees, with high probability, the identification of each similar Bloom filter pair. Our experimental evaluation, using four real-world data sets, shows that the proposed schemes outperform four state-of-the-art methods by achieving higher recall and precision, while being very efficient.