VTT Information Technology, Sinitaival 6, P.O.Box 1206,\
33101 Tampere, Finland

{veikko.ikonen, katja rentto}@vtt.fi\
<http://www.vtt.fi/tte/research/tte5/tte51/>

**Abstract.** This position paper presents experiences based on some
scenario evaluations of ubiquitous applications with potential users.
The purpose of these evaluations was to study how credible and useful
potential users considered the scenarios. Another purpose was to
identify the needs of different user groups for ubicomp applications and
let the participants innovate new uses for the applications. Scenario
evaluation is a usable tool for studying new concepts in the context of
everyday life. Scenarios enable designers to develop functional models
of real-life use of new products and to present design ideas to the
users, which could be difficult or expensive to prototype or simulate
otherwise.

1 Method

Scenario building is a good way to generate design ideas for new
products and to identify the possible users and contexts of use for the
product. Scenarios can be used to illustrate early design suggestions
(Carrol, 1995). Once you have become familiar with a current context of
use for existing products, you have to define the intended context of
use for the new product. The design team can develop one or more ideas
(or system concepts) for the new system. It is desirable to develop and
compare several concepts. The most feasible concepts are then submitted
as part of the user requirement specification. Scenario building aims to
predict how people could act in a particular situation. That is why it
is well suited for the design of new product concepts and for the design
of consumer products in the early phase of the development cycle, where
the context of use in not well-defined.

In our studies a scenario is defined nearly similarly as in concept
design. It is a tool for visualizing a possible way to act in a
particular situation. It helps potential users to understand imagined
applications and services of new technologies. Scenario evaluations are
a flexible way of quickly finding out user attitudes and needs. One
obvious benefit of scenarios is that they treat technology quite
flexibly: it can either be described in detail or the focus can be more
on the context of use. (Keinonen, 2000)

It is often easier to build scenarios with a group of people rather than
individually. That is why group methods, e.g., brainstorming, group
discussions and focus groups are well suited to scenario building.
Optimally the group should include people with different expertise, e.g.
designers, end users, application field experts, marketing people and
usability experts.

![](media/image8.wmf)

Fig. 1. Scenarios are a tool for the early phase of design (Kaasinen et
al. 2000)

The value of scenarios is that they make ideas more concrete for the
purpose of analysis and communication. The concreteness enables
designers and users to deal with complicated and rich situations and
behaviours in meaningful terms, and to understand better the
implications of particular design solutions for performing realistic
tasks (Carrol, 1995).

The material collected from the scenario evaluations is qualitative
(interviews, questionnaires, opinions) and it is collected by taking
notes and recording. The cost of the method depends much of the
techniques of scenario building and presentation that are used. Also the
analysis methods of the material can vary, and this affects the cost of
the evaluations. In our studies we have used written scenarios,
illustrated scenarios and scenarios that were acted and filmed (videos).
Interviews have been transcribed in some studies for structural
analysis.

2 Case studies

The KEN (Key usability and Ethical issues in the NAVI program) project
is developing a tool with which usability and ethical issues related to
a design of a personal navigation related products and services can be
identified. Ethical audit and usability design are both integrated into
the product design process: user needs and preferences always have top
priority. One of the tasks of the KEN project is to examine the
potential user and usage cultures. New navigation technology is not yet
commonly used and users in general are not familiar with navigation
services and technology. This is why we decided to examine potential
user groups by using scenarios.

The Future Home project was set up to define a solid, secure,
user-friendly home network concept that will be based on short range
wireless technologies. The project aims to define an open wireless
networking specification and will introduce IPv6 and Mobile IP protocols
for future home networks. The project will also specify and implement a
demonstration of a wireless home network with appliances and services
that use the capabilities of the network. The home networking and
intelligence services at home encompass a huge market potential for
manufactures and service providers. The usability studies of the Future
Home project, based on the defined scenarios, were performed before the
architecture design, in order to get early feedback to the proposed
applications and end-user services.

In most of the cases the interviewees received written scenarios some
days beforehand and were asked to read the scenarios before the
interview. Otherwise the scenarios were presented thoroughly at the
beginning of the interview. We explained with pictures and videos what
the future technological applications could be. Then we asked the
interviewees to imagine themselves as the user, to choose a role of the
actors in a scenario or to think emphatically of some other actor. Then
each scenario was discussed step by step. After each scenario, the
interviewees were asked to express their ideas and opinions, consider if
they would use the features presented in the scenario or not, and
present further ideas of how to improve the feature. The interviewees
were also asked if they had come up with some additional requirements or
features, which had not been mentioned in any scenario.

3 Issues

Illustrating the scenarios with pictures or videos was found a good
means to clarify the concepts presented in the scenarios and to lighten
up the stories. Some stories in the scenarios were probably too long and
too complicated for the evaluation context. In general, 3-5 scenarios
were an appropriate amount of stories to be evaluated at a time.

Terminology of the new technological applications was found difficult
e.g. the language and the terminology used in the KEN project\'s
accompanying letter that was sent to the participants before the
interviews were commented odd. Scenarios of course clarify the meaning
of the concept but still one has to be careful when launching new
services and devices -- is it better to use existing and familiar terms
or to create a brand new terminology? However, it is not always possible
to use existing terms. Strange terminology makes it difficult for users
to see the point of the story. Especially elderly users gave a lot
negative feedback in Future Home project about the scenarios. Strange
words, even when explained to them, gave somewhat negative nature to the
stories.

The scenario method could be time-consuming depending on how extensive
material you want to collect and how detailed analyses you want to make.
If there is more than one group of researchers working on the same
scenario evaluations it should be ensured that the procedure of the
evaluation and the questions (e.g. after translation) are similar. In
the Future Home project it was problematic to analyse the functionality
presented in the stories along the scale \"would use -- would not use\"
when the users could not give so exact answers. A typical problematic
answer from the analyst\'s point of view was e.g. such that the user
would like to use the function but not in a way presented in the story.
Or that the user would use the function if it would also do something
else. The real problem is how to analyse the answers unambiguously and
how to report and represent the interviews concisely.

Group discussions and interviews in scenario evaluations brought up the
real need of new technological applications for some users in particular
situations. The results of our studies can give valuable clues for how
novel technological applications should be developed for different kinds
of user groups. Although the results cannot be used as a market
analysis, this kind of approach can give remarkable suggestions to the
marketing: how the concepts should be presented for different kinds of
user groups and what kind of user attitudes can be expected.

References

Carrol, J. M. (ed.) 1995. Scenario-Based Design. London: John Wiley &
Sons.

Kaasinen, E., Kantola, K. and Olphert, W. Human-Centred Design Process.
In

Concejero, P. et.al. Usability in the Information Society - How to
design

user-friendly products and services. USINACTS project. European
Commission.

(CD-ROM) ISBN: 84-89900-23-x. March 2000.

Keinonen, T. 2000. "Pieniä tarinoita pienistä puhelimista" \[Small
stories of small phones\] in Keinonen, T. (ed.) Miten käytettävyys
muotoillaan? \[How to design usability?\] UIAH, Helsinki in Finnish.

Future Home project web page.
<http://future-home.vtt.mediapoli.com/fh/public/>

Ken project web page. <http://www.vtt.fi/tte/projects/ken/>