15. A system comprising: one or more computers configured to perform operations including: receiving a first collection of n-grams of a first natural language and a second collection of n-grams of a second natural language, the first and second collections of n grams being associated with one or more probabilities; using the first and second collections of n-grams and the associated probabilities to generate a plurality of randomized ranked collections of n-grams for each of the first natural language and the second natural language, each ranked collection of n-grams of the plurality of randomized ranked collection of n-grams having an ordering of n-grams according to a rarity of the n grams in the respective first collection and the second collection of n-grams; using each of the plurality of randomized ranked collections of n-grams to determine a plurality of signatures, each signature corresponding to a text of a collection of texts; and using the plurality of signatures to identify candidate text pairs within the collection of texts, the collection of texts including a plurality of texts in the first natural language and a plurality of texts in the second natural language.
20. The system of claim 15 , where identifying text pairs further comprises: comparing each signature corresponding to text in the first natural language with a plurality of adjacent signatures corresponding to text the second natural language according to a lexicographical ordering of signatures.