Istvan Hajnal is a veteran of more than 20 years in the fields of data analysis, survey methodology and market research. First at the University of Leuven, Belgium and then about 10 years with The Nielsen Company, the world's largest Market Research Company. Istvan is a Data Scientist for Hajnalytics. He received a master's degree in computer science (Leuven), a master's degree in quantitative applications in the social sciences (Brussels) and finally a Phd in Social sciences from the University of Leuven. He blogs about Data Science but occasionally also on management and leadership in general and the Market Research Industry in particular.