Iterative design whereby a product is designed, modified, and tested repeatedly.
User-centered design techniques
Focus group research
Design (structured) walk-through
One or more representative users on the design team itself.
Typically used for the development of in-house systems.
The representative users can become too close to the design team.
Focus Group Research
The very early stages of a project in order to evaluate preliminary concepts using representative users.
Simultaneous involvement of more than one participant.
To explore a few people’s judgments and feelings in great depth, and in so doing learn how end users think and feel.
To understand the preferences of a broad base of users about an existing or potential product.
It can use larger samples to generalize to an entire population.
Any time in the life cycle, but early stages are better.
Languages must be crystal clear and understood in the same way by all readers.
Design (structured) walk-throughs
First developed by IBM
To explore how a user might fare with a product by envisioning the user’s route through an early concept or prototype of the product.
Guide & monitoring
Users are shown an aspect of a product on paper and asked questions about it.
Critical information can be collected quickly and inexpensively.
Ex) Menu system, table of contents in HELP.
Repeated conducts without big expense
A review of a product or system, usually by a usability specialist who has no involvement in the project.
“ Double” specialist (usability and the area) is more effective than a usability expert.
Comparing the design of a product against checklists of standards.
Employs an iterative cycle of tests intended to expose usability deficiencies and gradually shape or mold the product in question.
Review of a product that has been placed in its natural setting, such as an office or home, just prior to release.
Advantage: the exposure of the product to actual working conditions
Disadvantage: the loss of control over the data collection – minimize the effectiveness by “let us know what you think”
Conducted after formal release of a product
Collect data for the next release, using surveys, interviews, and observations.
Goals of Usability Testing (1)
Of course, to ensure the creation of products that:
Are easy to learn and to use
Are satisfying to use
Provide utility and functionality that are highly valued by the target population
Goals of Usability Testing (2)
Creating a historical record of usability benchmarks for future releases.
Minimizing the cost of service and hotline calls.
Increasing sales and the probability of repeat sales.
Acquiring a competitive edge since usability has become a market separator for products.
Five Usability Attributes (1)
The system should be easy to learn so that the user can rapidly start getting some work done with the system.
The system should be efficient to use, so that once the user has learned the system, a high level of productivity is possible.
The system should be easy to remember, so that the casual user is able to return to the system after some period of not having used it, without having to learn everything all over again.
Five Usability Attributes (2)
The system should have a low error rate, so that users make few errors during the use of the system, and so that if they do make errors they can easily recover from them. Further, catastrophic errors must not occur.
The system should be pleasant to use, so that users are subjectively satisfied when using it; they like it.
Limitations of Usability Testing
Testing is always an artificial situation.
Test results do not prove that a product works.
Participants are rarely full representative of the target population.