SubWordTokenizer applies learned byte-pair merge rules to character-split text, producing whole words, partial words, or individual characters. It combines compact vocabularies with coverage for rare words. section 14.2.2
Moby Dick tokenizer
A 2,000-token vocabulary built from Moby Dick can tokenize every word without [UNK]. Common words remain whole, while rare words fall back to smaller subwords or characters. section 14.2.2
