Children Workload Experience during Usability Evaluation in different Settings
Mohammadi A. Khanum
PAHER University
Udaipur, India
Akheela.khanum@gmail.com
Munesh C. Trivedi
Dehradun Institute of Technology
Greater Noida, India
Munesh.trivedi@gmail.com
Abstract— In this paper, we investigate the effect of physical
context on behavior of the testers during usability evaluation.
Usability evaluation is performed on 54 children by exposing
them to four different settings. The four settings comprise of
lab testing using constructive interaction and think-aloud
protocol, and field testing using constructive interaction and
think-aloud protocol.The behavior of the children is evaluated
in terms of the workload they experience. NASA-TLX
workload measurement scale is used to assess the subjective
workload on the children. The results of the evaluation show
partial support to our hypothesis, which says that settings
affect the way children behave and perceive a testing situation.
Keywords- usability evaluation; children; behavior; physical
context; think-aloud; constructive interaction ;NASA-TLX
workload;
I. INTRODUCTION
Context is a term defined differently by different people.
For example, Brown et al. [1] define context as “location,
identities of the people around the user, the time of the day,
season, and temperature”. Ryan et al [2] define context as
the “user’s location, environment, identity and time”. Hull
et al [3] included the entire environment by defining context
to be “aspects of the current situation”. Schilit et al [4]
claim that the important aspects of the context are: where
you are, who you are with, and what resources are nearby.
Dey et al [5] define context to be the “user’s physical,
social, emotional or informational state”.
When evaluating the usability of any system, the behavior
of the user is very important. The factors which may affect
the user behavior needs to carefully considered because the
result of usability evaluations may vary in different settings
where the user may exhibit varying behaviors. Product
usability doesn’t take place in a vacuum; rather, it happens
in context [6]. The characteristics of the context (the users,
tasks, and environment) may be as important in determining
usability as the characteristics of the product itself.
Changing any relevant aspect of the context of use may
change the usability of the product [7].
Physical context comprise of the physical surroundings of
the users, it is the location, the place where usability
evaluation takes place. Physical context usually refers to
the environment in which user is tested. Natural
environment is the location of actual use of the system
being tested. Usability evaluation taking place in natural
environment is called as the field testing. Artificial
environment is the simulation of natural environment,
sometimes referred to as the controlled environment.
Usability evaluation carried out in artificial environment is
also referred to as laboratory testing.
Studies have shown that, as compared to evaluations
involving adult participants, children are mostly affected by
the context. Children show varying behavior when they are
tested in the laboratory environment and when they are
tested in the field. They feel relaxed and confident in their
own environment. The importance of the physical context
has been explored and studied by several usability
researchers. However, there is a lack of coherence in
understanding the context through psychological
perspective. Therefore, an understanding of the influence of
context and how it impacts the process of usability
evaluation is needed. In order to understand the relation
between the physical context and the individual’s behavior
we chose the widely accepted theory of behavior
settings.
The theory of behavior settings was introduced by Roger
Garlock Barker in late 1940s [8]. According to this theory,
behavior of an individual is influenced by the environment
in which he is. Barker continuously collected empirical data
from a small town in Kansas with less than 2000 people
from 1947 through 1972 based on which he developed the
theory of behavior settings. Behavior settings consist of two
elements, behavior, and milieu (setting). Behavior
comprises the way the people occupying the behavior
setting act towards each other. Milieu is a combination of
time, place and things and the milieu of a behavior
setting also exist outside of the behavior setting [9].
2013 International Conference on Communication Systems and Network Technologies
978-0-7695-4958-3/13 $26.00 © 2013 IEEE
DOI 10.1109/CSNT.2013.170
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