4. A computer readable storage medium on which is embedded computer software, the software comprising executable code for causing a processing system to execute steps comprising: applying an essay to a plurality of trait models; identifying a plurality of features associated with a vocabulary usage trait of the plurality of trait models; identifying multiple features associated with a discourse trait of the plurality of trait models, wherein the identifying multiple features comprises identifying a thesis, a main idea, a supporting idea, and a conclusion; determining a plurality of trait scores based on the plurality of trait models, each trait score generated from a respective trait model; and assigning a score to the essay based on the plurality of trait scores.
5. The computer readable medium of claim 4 , wherein the method further comprises: determining a content vector score based on a plurality of cosine values associated with the vocabulary usage trait; identifying a relatively high cosine value of the plurality of cosine values; and identifying a vector length based on a plurality of vectors associated with the vocabulary usage trait.