Nowadays an increasing number of persons needs (or decides) to retrieve information and to be contacted by everyone in every moment.
New technical infrastructures allow people to be always connected to a network (that can be both Internet or, as an example, a corporate intranet), with high speed, reliability and improved devices.
The access to information is mediated by various devices and interfaces that are still not enough investigated from an human–computer interaction perspective.
In this phase, usability testing plays an important role, as different devices and different interfaces can involve different interaction problems to be investigated.
According to Myers, Hudson, and Pausch this is not completely true, as most of the devices share the same graphical user interface:
"Almost all applications on Windows, Unix or the Macintosh look and work in a very similar fashion, primarily using a small set of
constructs invented 15 or more years ago. The specific techniques of graphical user interfaces that were first shown to have tremendous commercial impact by the Macintosh (starting in 1984), have been widely adopted with only small variations, and a relatively slow growth of new techniques.
Open Issues
This stability has had important positive benefits. For end users, the consistency of interfaces now available makes it possible for them to build skills which largely transfer between applications and platforms – knowing one graphical user interface provides skills that apply to many others. For tool builders this relative lack of change has also allowed them to go through significant refinement of concepts. In many respects tools have been able to mature and ‘catch up’ with an otherwise moving target.".
Differing from this position Lanfranchi (2003), states that new media like sub-notebooks, palmtop PCs, cellular phones are very different from desktop computers and their diffusion requires new efforts in usability research.
Remote Web Usability Testing
C h a p t e r V I I
Remote Web Usability Testing
Remote usability testing has been defined as "a usability evaluation wherein the evaluator, performing observation and analysis, is separated in space and/or time from the user" (Hartson et al, 1996).
In fact remote usability testing can be considered as a way to exploit the increasing power of the Internet and networks architecture to reach the users in their natural work or home settings, asking them to perform an evaluation test without going to a laboratory.
Remote usability testing can be considered a way to perform automatic usability evaluation.
In 1995 Balbo distinguished four main approaches to usability evaluation automation:
• nonautomatic: methods that require a specialist that conduct the evaluation
• automatic capture: software that capture data about the user while she is performing the test
• automatic analysis: methods that are able to identify automatically usability problems
• automatic critic: methods that are able to automatically suggest improvements
In 2001 Ivory and Hearst expanded Balbo classification to consider the effort required to effectively perform the test.
They considered that the required effort to perform a usability test could be:
Remote Web Usability Testing
• minimal: no effort is required to the evaluator
• model development: the evaluator should prepare a user model or a list of specification to be used during the test
• informal use: the user should perform freely chosen tasks
• formal use: the user should perform selected tasks.
Usually, remote usability testing are performed with software that allow to evaluate the usability of web sites gathering information from remote users, with a different required effort depending from the usability evaluation approach selected (see Chapters III, IV, V) . This approach does not differ so much from the in loco strategy (described in 6.1 ):
usability evaluation is conducted in a real world environment, but without the need to displace researches and technologies in loco.
The key advantage of remote testing usability is that an high number of test users can take part, with little incremental cost per participant, allowing to overcome the trade-off between the number of participants and the cost of the test suggested by Nielsen (n.a.).
As already mentioned, Nielsen suggests that the ideal number of users required to perform an usability test is 5, since 5 users are enough to identify the majority of usability problems of a web site. The approach is based on the economical aspect of usability testing: the number of test users should be chosen accordingly to the available budget. Every extra user is an incremental variable cost that should be balanced by the extra incremental number of relevant usability problems that are found out. After various researches Nielsen found out that after 5 users, the incremental cost per user is higher than the contribute he can convey. Hence, testing an higher number of users could be interesting but can be avoided if the budget is limited.
Remote Web Usability Testing
If we consider the economical aspect of usability testing we can recall the main principle of economic science, that states that the cost of a work is determined by the fixed costs plus the variable costs. Using remote web usability testing the total cost of the test is mostly composed by fixed costs (e.g., deciding what to analyse, which tasks have to be performed, analysing the results) while the variable costs (the subjects) are reduced, since it is not costly to reach users remotely and make them perform the test. The variable cost is higher, if we have to ask an user to come to a laboratory, since the user cannot go to work and she has to afford mobility costs (or we have to reach him at home or at work). If we are making a remote test, the time required to perform it and its cost are lower, since the users does not to move from her setting, she does not miss the work and travel costs and facility fees have not to be paid. Moreover, the user can select a time to perform the test that suits her individual schedules.
Remote usability testing improves a participatory and iterative design, since a test can be frequently repeated and data can be gathered continuously.
It is also easier to contact respondents in different geographic areas and to select a time scheduling that is suitable for them.
Moreover a remote approach allows performing test in environments where access is difficult, time-consuming, or costly.
If we consider performing a test for evaluati ng the usability of web site for long-term hospitalised children, it is impossible to ask the subjects to come to a research laboratory and it is also very difficult to access to their environment, the hospital, since often these children live isolated and they cannot have contact with other persons. In such situations it is impossible both to perform laboratory and in loco tests, while it is possible to use a remote web usability testing approach, eventually accompanied by an usability inspection.
Remote Web Usability Testing