Disclosed are methods, apparatus, systems, and computer-readable storage media for identifying similar labels. In some implementations, one or more servers maintain a plurality of data entries in one or more database tables storing textual data, each data entry of a first portion of the data entries including: a text sequence, a label, and a text-to-label association score, and each data entry of a second portion of the data entries including: a first label, a second label, and a similarity score. The one or more servers analyze the data of the first portion of data entries to generate one or more pairs, each pair including information identifying a first label and a second label. The one or more servers calculate a similarity score for each of the one or more pairs and store the respective similarity scores in the second portion of the data entries.