Archives For HCI

Today let’s talk about cognitive models. That’s really a fancy term for how someone thinks about something. It’s taking an action or goal and creating a model in your brain about how you would perform that action. For example, if someone said to “make dinner” then that would mean different things to different people. Some are going to throw something in a microwave, others craft something from what’s in the pantry, others go to a restaurant, and others pull out their cookbooks to pick something appetizing. The cognitive models for different people can differ for the same activity.

Introspección > Música. (CenTerO / JaguariTech)

Introspección > Música. via CenTerO / JaguariTech (Flickr)

As UX professionals, we need to know the cognitive models of our users. If we’re designing within that model then their experience becomes much more enjoyable and seamless than designing something that they have to explore and discover to build a new model. Sometimes that can be a good thing but we still need to know cognitive models in order to be intentional about when we break that rule. Let’s look at some questions to ask when designing and accounting for cognitive models.

Continue Reading…

Usability Testing, Why?

December 6, 2010 — 1 Comment

Testing? Ew, gross. That sounds like something I loathed during my school years. No, no, this is something else. Usability testing is putting designs up against real users to see how they perform. Let’s take a simple example as an illustration.

A/B Testing

A/B Test

This is a simple A/B test. Even testing as simple as this can yield some pretty impressive results. We’ll save the different kinds of testing for a different article but we’ll look at why testing should not be skipped in any design process.

Continue Reading…

Parallax. It may be an unfamiliar term to many. It’s defined as the apparent displacement of an observed object due to a change in the position of the observer. For example, a driver may look at a speedometer and it reads 65, but when the passenger looks on it appears to read a different speed due to the difference in angle they are viewing the speedometer from. There’s nothing different with the speedometer itself, but just the angle it is viewed from makes it appear different.

We need to view our designs from the parallax as well. Well, to clarify, we need to view them both head on and from the parallax as well. Doing this doesn’t change the content but gives us a different viewing angle of that content from which we base our designs. This can mean many different things. We can adapt this to mean designing a web app to fit a mobile experience or we can adapt it to mean moving a local machine experience to a network-based experience. Or maybe it’s just a simple (or not so simple) redesign. It’s really just about taking the same basic problem and adapting that problem for some difference in an environmental variable, but the purpose is to use these different angles to feed various POVs into our designs to improve the user experience.

Continue Reading…

For anyone interested in some of the true theory behind HCI principles (we don’t just say stuff is better because we think it is) then this post is for you. We’ll explain what Fitt’s Law is, the basic idea behind it, and how that information can be applied practically to your applications and designs.

These design’s are giving me Fitt’s!

Fitt’s law is a mathematical formula that can calculate the difficulty it is to use two UI elements given the size and distance and of those elements. The formula is written as:

MT = a + b log2(1+D/W)

Continue Reading…