Erratum

In the publication of this article [1], there were errors in:

The first error: In table 6 the headings of column 8 and 9 incorrectly indicate ‘problem’. Should instead read: ‘probability’.

The second error: An additional second address of the first author was missing: ‘School of Economics, Huazhong University of Science and Technology, Wuhan, Hubei 430074, P.R. China‘

Should instead read: 1School of Economics, Huazhong University of Science and Technology, Wuhan, Hubei 430074, P.R. China, 2Department of Economics, University of Jos, Jos, Plateau State 930001, Nigeria.

This has now been included in this erratum.