Consumers much prefer getting something for free than getting something for less, according to new research on the psychology of discounting by a team of researchers led by Akshay Rao of the University of Minnesota's Carlson School of Management. What's the best value for money -- "50% extra free" or "33% discount"? According to the research, many consumers aren't aware both offers are the same. Instead, most assume that the extra free product is the better deal.