Text and Data Mining valid from 2016-08-24
Received: 4 February 2016
Accepted: 23 June 2016
First Online: 24 August 2016
Change Date: 28 September 2016
Change Type: Update
Change Details: A correction has been published and is appended to both the HTML and PDF versions of this paper. The error has not been fixed in the paper.
: The authors declare no competing financial interests.