If you were looking for a particular toy, and saw that it was sold out, but something similar to it was still in stock, would you buy the similar item? According to a recent study conducted by the University of Alberta School of Business, shoppers become more likely to purchase a certain item if they see that a similar item has sold out.

Why is this? The empty shelf gives the sold-out product a certain level of desirability, which “transfers” to the similar product as well. If one product is desirable, then the one that is like it must be desirable too. And if one is sold out, the other will likely be selling out soon, thus creating a sense of urgency and making you want to buy it now instead of later.

Stores can leverage this phenomenon to their advantage if they create an illusion of scarcity. If they make an item appear to be difficult to get, it makes people more likely to buy it on impulse, or immediately after it comes out, because it’s so sought after. I’m sure we can all think of items we’ve suspected of being “falsely” scarce…the Nintendo Wii or the Apple iPhone come to mind, as well as the popular Christmas toys of each holiday season. The harder an item is to find, the more our kids just have to have it.

When customers know that there are limited supplies of an item left, they are more likely to buy “now” because they know it may not be in stock later. How do empty shelves affect your own holiday shopping? Do they make you want to buy a similar product just because one is sold out and must be popular? Or would you rather wait until the other product is back in stock and you’re ready to buy?