10. The method of claim 1 , further comprising jointly training the character sequence model, word sequence model, and trait model on a collection of text sequences, each labeled with a respective value for at least one predefined trait.
11. The method of claim 10 , wherein the training comprises, for each of a plurality of predefined traits, jointly training a respective character sequence model, word sequence model, and trait model for a respective one of the plurality of predefined traits.