Particularly in unfamiliar situations, people make value judgments based on the information available, but they do not treat information equally. Dan Ariely provided a great example from The Economist, which offered three types of 1-year subscriptions, as follows:

• a Web subscription to Economist.com, for $59
• a print subscription, for $125
• a print and Web subscription, for $125

Why offer a print subscription on its own at all? People can be very bad at judging the value of things, particularly things they buy infrequently. They rely on contextual information to understand when they are getting a good deal. Ariely conducted an experiment in which he presented these three options to a group of 100 MBAs, and 84% chose the print and Web subscription, with all others choosing the Web‑only option.

He then conducted a second study with a different group of 100 MBAs, presenting only two options:

• a Web subscription to Economist.com, for $59
• a print and Web subscription, for $125

Now, only 32% chose the print and Web subscription. With three options available, people anchored on the print subscription, which made the print and Web subscription look much, much better by comparison. They didn’t know whether $59 for a subscription to Economist.com was a good deal, but choosing between just two options was easy!

UX designers frequently hear variations on this: But we have smart users! They may be smart, but the basic wiring of people’s brains is always the same. People make judgments based on the information available to them, and UX designers control the information that a Web form presents.