iScale: Studying Long-Term Experiences through Memory - Modeling Users' Experiences with Interactive Systems - page 99

5.3.2.4 Control

Most participants stated that the iScale tools provide more overall control. First,
eight out of the twelve participants found the constrained interaction a positive as-
pect of iScale, providing better interactivity , as it consumes less resources, thus
providing them better control of the output (4 participants) and enabling them to
focus on recalling their experiences (4 participants).
Second, participants differentiated iScale from FHG in terms of the ability to
modify the graph while new experiences are recalled. Some participants further dif-
ferentiated between the two iScale tools in terms of modifiability.
Third, seven out of the twelve participants acknowledged that the value-account
tool provides a better overview of the full timeline, and, thus, temporal overview
enhancing their recall process.

5.3.2.5 Interplay Graphing-Recalling

Five participants in total mentioned temporal linearity as a property that differen-
tiated free-hand graphing and the constructive iScale from the value-account tool.
Most of those participants mentioned that recalling events in a step-by-step order
helped them in recalling more events, while some of them were negative towards
value-account as they felt that it constrained them when recalling events due to a
focus in compiling a coherent story.
Similarly, five participants highlighted that the concurrency of graphing and re-
porting, that was a feature of the constructive version of iScale, enhances the output
of both the recall and the graphing process.

5.3.3 Discussion

As expected, free-hand graphing was found to be more expressive than iScale due
to the increased degrees of freedom in graphing as well as due to its ability to eas-
ily annotate graphs. However, participants also reported properties that were not
present in the FHG, such as the two-step interactivity and modifiability of the elec-
tronic graphs that resulted in a better interoperability between the graphing and the
recalling activity. Participants also reported benefits for both the constructive and
the value-account iScale. The value-account version provided a temporal overview,
which influenced both graphing and recall. The constructive approach provided ben-
efits, such as the chronological order and concurrency between graphing and report-
ing which had a positive impact on the recall process.
The need for graphing non-linear and discontinuous curves was limited, while
most non-linear curves could be approximated by two linear segments. The need
for annotation was highlighted by participants in the post-use interviews and two
forms of annotation were added to the tool: (a) a timeline annotation that allowed
users to set the start and end date of graphed segments, thereby splitting the timeline
in specified periods, and (b) a visualization of experiences along the respective line
segment that they belong to, with a brief identifier for the experience (see figure