The HOO 2012 Error Type Definitions

The HOO 2012 Error Type Definitions


The set of error tags we use in HOO is based on the Cambridge University Press Error Coding System; this is copyright to Cambridge University Press and may only be used with their written permission. The coding is used by CUP to annotate the Cambridge Learner Corpus (CLC), which informs English Language Teaching materials published by CUP. The scheme is discussed in detail in [Nicholls, 2003].

The HOO coding scheme uses a different syntax from the CLC, but has essentially the same semantics. The HOO encoding allows for optional and multiple corrrections, which CLC does not, and allows for distinct edits to be related to each other by means of what we call consistency sets. HOO also adds a CC tag for compound changes. None of these supplementary features is made use of in HOO 2012.

The Error Tags

The CLC scheme accommodates around 80 distinct error tags. For HOO 2012, we use only six of these, shown with examples in the table below.

Error CodeDescriptionExample
RTReplace prepositionWhen I arrived at London
MTMissing prepositionI gave it John
UTUnnecessary prepositionI told to John that ...
RDReplace determinerHave the nice day
MDMissing determinerI have car
UDUnnecessary determinerThere was a lot of the traffic


Nicholls, D. [2003] The Cambridge Learner Corpus—Error coding and analysis for lexicography and ELT. In D. Archer, P. Rayson, A. Wilson, and T. McEnery, editors, Proceedings of the Corpus Linguistics 2003 Conference, pages 572–581, 29th March–2nd April 2001.

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