In the Results and Discussion section, second last paragraph, the text which states "It is only due to the specific selection of clauses in the current investigation that such high inter-subject agreement arose" should read as "low inter-subject agreement". We apologise for this error.
Correction
1 October 2015
In the Results and Discussion section, second last paragraph, the text which states "It is only due to the specific selection of clauses in the current investigation that such high inter-subject agreement arose" should read as "low inter-subject agreement". We apologise for this error.
Competing interests
None declared.