Shoppers make irrational choices; that’s a conclusion you can draw from new consumer research from psychologists at the University of Chicago School of Business. The study looked at the influence of numbers on buying choices. It found that people chose things in a non rational way.

For instance, when shown pictures produced by cameras they chose the camera which led to the best looking image. However, when shown the numerical resolution of the camera they chose a product based on that number – even if the pictures were rated worse than a camera with a lower resolution.

Additional studies on the thickness of crisps and the number of air bags in a massage cushion also produced similar results. In other words, in spite of experience and other knowledge, people made their purchasing decisions based on specifications – which often contained no valuable additional information.

Manufacturers know, for instance, that if you stamp “10 Megapixels” on the front of a camera it is sold more often than one that only claims 6 Megapixels. But a photographer would explain that the quality of the lens is much more important than the raw number of megapixels. In other words, consumers appear “fooled” by the numbers.

So what does this mean if you are trying to sell products and services online? It suggests that if you add specifications and numerical information, you are more likely to make the sale. For instance, let’s say you are selling a training course online. Instead of saying it’s a “one-day” course, instead say it’s “480 minutes of learning”; instead of saying there is a “course manual”, say there are 128 pages of documentation containing well over 25,000 words. In short, give lots of numbers and you are likely to have greater influence over selling something online.