Understanding how the brain works is important in interaction design not only to be able to craft experiences that support the way people think, but also to avoid common biases in our own brains as we make design decisions. One bias that sneaks into design problems all the time is called the “availability heuristic”, or the tendency to judge how important or common something is based on how easy it is for us to think of an example. For example, if you were to ask me how the baby boomers react to technology, the first example that jumps to my mind is my mother who happens to be a complete technophile and Apple fangrrl. Because of the ease with which that example comes to mind, I am at risk of grossly overestimating technical interest and ability amongst the baby boomer population.
If you’re involved in the design of products, you run into this problem all the time. Stakeholders use their own most easily-retrieved examples to compare against, whether it’s the CEO who is influenced by the pundit he read that morning, or the product manager who knows that one guy who is just like your target market, or the designer who is really designing for himself — the self being the extreme “available example.”
Availability biases leads to poor design decisions because they are based on single, potentially skewed, examples; they also result in thrash because each individual involved in the design has his or her own reference example, making consensus difficult.
Effective research is only the first step toward avoiding this problem. Properly conducted ethnographic research will provide an understanding of the needs, goals, and behaviors of your target market, but it won’t solve the problem of availability bias on its own. It is too easy for designers and stakeholders to be influenced by, say, the most recent interview conducted, or the most memorable one.
Fortunately, we have a well-honed tool to elegantly overcome this problem: the persona. A well-crafted, research-based persona is an archetype that smooths out the idiosyncrasies of real individual people while retaining the patterns of needs and behaviors in the target market. At the same time, a persona retains enough human detail to feel like a real person. With practice and dedication, the persona becomes the first example that comes to mind. You still suffer from availability bias, but the bias is in favor of reality.
Incidentally, I got to thinking about the availability bias when Chris Noessel pointed me to this video on YouTube. Be forewarned: the tune is catchy and likely to cause a nasty case of earworm . Bradley Wray, FTW.
What tools do you use to overcome cognitive biases in your work?
Jenea Hayes is a Design Director and Cooper Professional Education instructor at Designit San Francisco.