1. Department of Economics, Business School, Durham University , Durham, DH1 3LB, UK
2. Department of Economics, Accounting and Finance, Universidad Politécnica de Cartagena (Murcia) , 30201, Cartagena, Spain
3. Department of Quantitative Methods, Modern Languages and Law, Universidad Politécnica de Cartagena (Murcia) , 30201, Cartagena, Spain