Text and Data Mining valid from 2018-04-09
Received: 26 November 2017
Accepted: 7 March 2018
First Online: 9 April 2018
Change Date: 1 May 2018
Change Type: Correction
Change Details: The original version of this Article contained an error in the spelling of the author Hongfei Li, which was incorrectly given as Fei Hong. This has now been corrected in both the PDF and HTML versions of the Article.
: The authors declare no competing interests.