iScale: Studying Long-Term Experiences through Memory - Modeling Users' Experiences with Interactive Systems - page 89

5.2.3 Graphing Affect as a Way to Support the Reconstruction of

Experiences

Imagine being asked to provide a graphical representation of how the global eval-
uation of your mobile phone changed over time on a timeline, which starts at the
moment of purchase and ends in the present. There are a number of ways doing this.
The aforementioned CORPUS technique - somewhat atheoretically - recommended
starting from the momentary perception, comparing it to the beginning of prod-
uct use and then recalling specific experiences. The presented theoretical positions
above, however, provide clearer, more theoretically grounded suggestions of how to
proceed. The constructive approach suggests starting from the beginning, recalling a
piece of experiential information (e.g., an episode, a situation) and reconstructing an
affective response and the according evaluative judgment (see e.g., Hassenzahl and
Ullrich (2007) for the relation between affect and product evaluation) to this piece
of information. This will then cue the next piece and so forth until change over time
is reconstructed. The value-account, however, suggests starting with the affective
information, that is, recalling the change of affect and evaluation over time first, and
using the general shape of this to recall more specific experiential information.
Obviously, both approaches can be supported by a tool. However, using the one or
the other procedure may impact the results. To study potential differences, we created
two different versions of iScale, the constructive and the value-account iScale.

5.2.4 iScale

Experience reconstruction with iScale starts with two questions: a) “What was your
opinion about the product's [particular quality] just before you purchased it?”, and
b) “How did your opinion about the product's [particular quality] change since
then?” The participants are then presented with a timeline that starts at the mo-
ment of purchase and ends in the presence. In general, participants graph linear
segments that represent an increase or decrease in their perception and evaluation
over a certain period. Each line segment is associated with an identifier, displayed
below the segment (figure 5.2a). A participant can click on the segment to report
one or more experienced events, which are perceived as a cause of change. For each
experience report, the participant can provide a brief name (identifier), a more elab-
orate description of the experienced event (a narrative), and respond to a number of
event-specific questions (figure 5.3a). For the goals of the present studies, we asked
participants to recall a) the exact time that the event took place, b) the impact of
the event on the participant's overall perception and evaluation, and c) the partici-
pant's confidence on the exact details of the report. However, these questions can be
adapted to particular research interests.
The two versions of iScale differ in the way graphing was used to support the
reconstruction of experiences from memory. More specifically they differed in the
progression of graphing (feed-forward versus top-down), and, the existence or ab-
sence of concurrency between graphing and reporting.