1. A system comprising: a processor; memory storing instructions that, when executed by the processor, configure the processor to: generate one or more candidates from an input sequence, the input sequence comprising a contiguous sequence of characters, wherein each candidate comprises two or more terms separated by one or more term boundaries; search for one or more terms of each candidate in stored sequences of terms, each sequence of terms having a corresponding probability of occurring; and assign a probability to each candidate based on the search.