In a study that became known as “The Jam Experiment,” a supermarket laid out six varieties of jam on a display table one day and 24 varieties on another day.

When there were six choices available, 30 percent of the customers who sampled them made a purchase. But when there were 24, only 3 percent of the shoppers made a purchase.

Having more choices makes choosing less easy, concluded Sheena Iyengar, a co-publisher of the study and a professor at the Columbia Business School.

I am fully aware that consumer psychology has little to do with anyone’s political choice. Still, with a record nine candidates running in the upcoming Liberal Democratic........

© The Asahi Shimbun