Chapter III, 7th August 2010 - 13th August 2010
Avoid Being Embarrassed by Your Error Messages
This week's first instalment begins with an often forgotten issue with software: the usability of software gone wrong. Let's face it: all non-trivial software has bugs. And humans are more than accustomed to live with unexpected situations: it's what cognitive psychologists call inference.However, several times, UIs provide dead ends when faced with an erratic behaviour. It becomes significantly troublesome to cope with such issues, e.g., cryptic error messages, error numbers, etc. No amount of inference by a human being (other than the programmer who coded it) will be able to discern the problem conveyed on most error messages. This article on UX Matters discusses some of these behaviours of software. The key message from this article is: Think about error messages as part of a conversation with users.
Visualizing Fitts’s Law
Fitts's law. The golden treasure of Usability. One of the few mathematical formulas than can quantify a usability property. For those who don't know or recall what this law states, it's explained in a few simple terms: the smaller the clickable area, the more difficult it becomes to reach it with the mouse quickly.This introductory article at Particletree describes thoroughly the properties of Fitts's law, how it can be applied in a 2D scenario (since it was originally devised just for one dimension), and all with the aid of interesting and appealing pictures.
Whether you are a novice or an expert in the UX field, I strongly recommend you to read this article. Well written, straight to the point (pun intended), and it even discusses a bonus point: screen edges (spoiler alert: it's all in the infinite dimensions).
Choices should always be limited to 7+/-2
This meta article on UX Myths provides several links to the discussion and debunking of one of the greatest myths in usability: the one that states that since people are only able to memorise few things in their short-term memory, they should be presented with lists with limited size.It's not enough to stress this fact once. It should be repeated ad nauseum. By having lists presented visually, sighted users do not need to (and will not) memorise them, since their affordance is immediate.
Even for blind people, who depend greatly on short-term memory when interacting with information, can cope with big lists of information if they are familiar with the subject (citation needed, but it comes from several observations on usability studies we performed with blind and partially sighted users.).
The $5 Guerrilla User Test
It seems that this week's articles are particularly focused on classical usability/UX topics. This last one discusses guerrilla usability testing: stop at a caffee and ask someone if they can help you with a small set of tasks.This kind of tests challenge the myth that all usability tests are hard to make, require a lot of users, expensive equipment such as 10000€ eye-trackers, etc. With the right conditions and proper planning, guerrilla usability tests can provide several answers about the UX of a software, and keeps people from skewing their actions for being inside an etheral usability lab.
The fun (dare I say, awesome) side of this article lays at a particular insight: Drunk people are a pretty accurate mimic of distracted, indifferent people.
(that's it for now. next week I'll definitely have more to share.)
