1. A processor-implemented method to build a trait model for essay evaluation, comprising: receiving at least one evaluated essay; identifying and extracting with a processor a plurality of features pertaining to one or more traits from the received at least one evaluated essay; wherein a trait comprises one or more features or feature sets and each feature set comprises one or more features; wherein the one or more traits comprise writing errors, discourse, or vocabulary usage; creating a plurality of vector files based upon the plurality of features; building the trait model for essay evaluation based upon the plurality of vector files; and evaluating the trait model, the evaluating including: mapping features of a new essay to the trait model by navigating a multi-branched decision tree, and wherein at each branch of the decision tree, a value associated with the features of the new essay is used to determine how to proceed through the trait model.