A major weakness of many existing essay scoring engines such as IntelliMetric (Elliot, 2001) and Intelligent Essay Assessor (Landauer et al., 2003) is that they adopt a holistic scoring scheme, which summarizes the quality of an essay with a single score and thus provides very limited feedback to the writer.
it is not clear which dimension of an essay (e.g., coherence, relevance) a score should be attributed to.