Tuesday, January 27, 2009

Nielsen's "Usability" and Some Questions (Part 3/3)

Nielsen says, “Peoples’ attitudes toward computers in general should probably be seen as a component of the social acceptability of computers rather than their usability.” One interesting outgrowth of this statement would be the fact that as time progresses and technology finds its way into true ubiquity, we will find fewer instances of true novices and social accessibility will increase regardless of a designer’s intent.
Where Jakob Nielsen discusses usability trade-offs several good comments surface, including the fact that one cannot design the perfect interface for all user types. Also, where other considerations, such as security measures, take precedence, ease of use sometimes suffers. This area naturally leads into section 2.5, where he discusses categories of users and user differences. This is an essential element to be covered in these beginning chapters. Figure three on page 44 shows the matrix of users’ experience which is also enlightening.
The way that Nielsen goes on to describe the systems as they pertain to the matrix is quite eye-opening especially if someone has never considered these interfaces from the perspective of the user. He also introduces the concept of quartiles in signifying which user is at the high end of a given spectrum or the lower end.
At the end of this chapter, Nielsen also mentions that it is not necessarily the best idea to permit the user to customize their own interface beyond a certain cosmetic point. This point is followed up in later chapters, but it does provide the context for additional questions.
How does one decide how much of an interface should be customizable (for example, in the case of Facebook versus Myspace)?

Nielsen's "Usability" and Some Questions (Part 2/3)

Memorability, on the other hand, is one of those elements that might not seem immediately obvious when user-testing first occurs, but many of us have experienced the loss of system proficiency after not having used a product for any extended period of time. I continue to experience some amount of anxiety when moving between Adobe products when the quick-keys for certain shared functions is not the same or when the interface (eg. in Illustrator) is different between a Mac and a PC. Additionally, whereas errors are also easily recognized as a hindrance to production, subjective satisfaction would seem to be a derivative of the other attributes for usability.
Does subjective satisfaction deserve to be an individual element or is it a derivation of the other attributes of usability?

Nielsen's "Usability" and Some Questions (Part 1/3)

What is usability?
One of the key concerns for Usability professionals is being able to answer the question “What is Usability?” According to Jakob Nielsen, usability can be defined by the following five attributes: learnability, efficiency, memorability, errors, and satisfaction. Each of these attributes would seem obvious once you read the list of them, but, of course, being able to come up with a complete and concise list is the difficult part. For each of these attributes, he then further explicates the details. In the case of learnability, I’m glad that Nielsen has differentiated between novice and expert users. However, he does not necessarily include level of comfort in mastering an interface. Holding usability to a higher standard would involve taking learnabilty to the level of mastery and a high degree of comfort. Currently “learning software” is the strongest bastion for these more stringent levels of learnability.
One question for this section would be:
How does one use leading edge teaching techniques to increase cognition and make learnability more core to usability?