1. School of Psychology; Keele University; Staffordshire ST5 5BG United Kingdom
2. Computer Science Department; University of Toulouse; IRIT UMR 5505 CNRS, 118 route de Narbonne Toulouse cedex 9 F-31062 France
3. Department of Quantitative Methods in Economics; Faculty of Economics; University of Information Technology and Management; Rzeszów, Sucharskiego 2 Rzeszów 35-225 Poland