Attention capture is involuntary. If a stimulus appears in your visual field, it will capture your attention regardless of whether you want it to or not. Two ways to capture attention Rapid luminescence captures attention – something turns abruptly bright Rapid appearance of a novel perceptual object captures attention – an object suddenly becomes...

Visual “pop-out” occurs when a unique visual target (e.g. a feature singleton) is present among a set of homogeneous distractors (source: Hsieh et al., 2011) Example: Adaptive tool-bar highlights things that they used before Assuming the system is pretty good at predicting what you need next, this is a very effective feature The problem...

The Hick-Hyman law demonstrates that the time it takes to make a decision is proportional to the logarithm of the number of options Given n equally probable choices, the average time T required to choose among them is approximately T = a + b log2(n) Applies only to cognitively simple decisions Carries important implications...

Fitt’s Law declares that performance is logarithmic. It utilizes an UI element’s ratio of distance (to it) to (its) width. A + B * log2(D/W) log2(D/W) is the index of difficulty in bits. 1/B is the index of performance in bits per second. Fitt’s Law can be used to calculate the difference in index...

A paper published in Nature in 1998 (http://bit.ly/1q8L83D) showed that neural control signals are corrupted by noise whose variance increases with the size of the control signal. Although that may seem like gibberish, our conversation in class boiled it down in a simple example: the greater the acceleration of your movement, the less accurate...

Going back to the ball example that we looked at in class, there was an instance where one ball “hit” another, and the second ball moved a couple of seconds after impact, while in another it moved right away. This touched on the point that in order for someone to conclude a causal relationship...

One design concept that was looked at in class today was creating metaphors. Humans are able to learn through target recognition, where the associate certain objects with their use cases in daily activities. For example, we examined the trash can icon that apple uses on their mac books. Obviously trash cans are used to...

A technique that allows the user to explore information by applying multiple filters.  Each facet corresponds to a property of the information, and you can specify a specific value or range of a facet to filter on.  In class, we learned the flight search site Kayak had faceted browsing, in which you could refine...

Interfaces that speak in the languages of what you are interacting with (i.e. files, photos).  They do not require much prior knowledge, expecting the user to recognize rather than recall the interface.  They also support rapid and risk-free exploration.  Actions within a direct manipulation interface usually has immediate feedback.  In lecture, Finder (file browser)...

This term originally comes from psychology and a psychologist named Gibson, but it is now primarily used in design. Essentially, this is that “we perceive in order to act.” What we see shows us how to act based on its communication with us. In early designs, affordances were very in-your-face, like the physical-looking ‘buttons’...