The “unit effect” makes 31 days seem better than a month
The human brain engages in all sorts of mental shortcuts in order to make quick judgements about the world, and some of them make us vulnerable to marketing. For example, consumers will readily attach weight to completely fictitious product statistics, preferring items with the most bogomips, even if they have no idea of what the significance of that figure is. That may be disappointing, but apparently it's even worse than that—even when they do know what the units are, people tend to prefer a bigger number. As a newly released study shows, people would rather pay for expedited service to get things in 31 days than they would to get it in one month.
The researchers involved in the new work cite an extensive list of some of the counterintuitive judgements people make when it comes to numbers. For example, we do dumb things when it comes to foreign exchange. When we shop in currencies with a favorable exchange rate, we tend to spend less, because handing over a large quantity of currency strikes us as overspending, regardless of the currency’s relative value. In the same way, we tend to overspend currencies with a high value.