The Magical Number Seven, Tax Collectors and Cellphone Designers
Recently I was paying some taxes. In France this is not as terrible as it sounds because the tax people have a most excellent website www.impots.gouv.fr where you can pay all your taxes online with just a few mouse clicks. The site is surprisingly effective and makes the chore of paying taxes if not exactly a pleasure then maybe less painful that it could be, though every mouse click still sucks away thousands of Euros. But there is one area where the site might be improved, and herein lies a very general lesson not only for website design but also for the design of mobile phones and other consumer products: the way they require you to enter long numbers without spaces. Fifty years have passed since George Miller wrote his landmark paper “The Magical Number Seven Plus or Minus Two” -- http://psychclassics.yorku.ca/Miller/ -- but the lessons have apparently not yet been learned. Following many experiments, Professor Miller discovered that the average human can process information in