The second keynote at the Human Computer Interaction conference in Lancaster was given by Jared Spool who talked about Breaking through the invisible walls of usability research. Jared is a very inspiring and entertaining speaker. If you have the chance to listen to him, take it!
One of the things he talked about was the fact that the usability techniques that are widely used today were in fact not designed for large amounts of users. We have all kinds of data about the users’ behaviors online, but can we really use that data in a productive way? As Jared said;
“there is a big difference between data and information, we don’t know what inferences to make from the data we have.”
He also gave examples from a couple of large american ecommerce sites that have millions of users every day. With traditional usability measures you, according to Jacob Nielsens report, can identify 80% of the usability problems with as few as five users. But if you have one million customers, then you could say that 200.000 of the customers would be annoyed. Imagine how much money’s worth of lost revenue 200.000 users is. So how many nines to we need? (90, 99, 99,999?) How many percent is enough? It is apparent that we need to find methods that can solve these problems with usability evalutations and testing.
Jared Spool visualizes how few users actually spend money on an ecommerce site, and how few users the company relies on for their revenue.
Jared also talked about the consequences that web 2.0 have had for web applications and communities. He talked about what things that make people want to use “extra functionality”, as for example review functionality; what things delight people. Things that are excitement generators today soon come to be expected in every application. And when, as Jared said, HCI becomes HHHHHCI; when social networks are widely used, things that delight us or aggravate us, spread very fast. So instead of thinking about the five user rule, think about this next time you plan a release of a new product or application: How many users can you afford to annoy?