Why emotional reactions are a better indicator of behaviour

As traditional methods of market research go into decline, what are the strengths and weaknesses of newer techniques that track real-time emotional responses and get behind the psychology of the consumer decision-making process?
The value of the data analytics market has grown by more than 350% over the past four years and has been a major contributor to the size and effectiveness of the UK research sector, according to a recent study commissioned by the Market Research Society and carried