Funding for this research was provided by:
Economic and Social Research Council (514695112)
Text and Data Mining valid from 2018-08-29
Received: 15 March 2017
Accepted: 30 July 2018
First Online: 29 August 2018
Ethics approval and consent to participate
: This study used only previously collected anonymised data from publically available datasets. Not applicable.
: Not applicable
: The authors declare that they have no competing interests.
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