Bryant and Briscoe (2018) addressed substitution errors such as non-words, morphology-, article-, and preposition-errors by creating confusion sets C(x i ) that contain possible (contextindependent) 1:1 corrections for each input word x i .
they relied on CyHunspell for spell checking (Rodriguez and Seal, 2014), the AGID morphology database for morphology errors (Atkinson, 2011), and manually defined confusion sets for determiner and preposition errors, hence avoiding the need for annotated training data.