User Experience Over Time - Modeling Users' Experiences with Interactive Systems - page 81

priori, but also quantifying their significance and understanding how these relations
changed over time.
In this view, experience narratives provide at least two kinds of information.
Firstly, each narrative provides rich insights into a given experience and the con-
text in which it takes place. Secondly, generalized knowledge may also be gained
from these experience narratives. Such generalized knowledge may be reflected in
questions like: how frequent is a certain kind of experience, what is the ratio of posi-
tive versus negative experiences and how does this compare to competitive products,
how does the dominance of different product qualities fluctuate over time and what
should we improve to motivate prolonged use?
This leads to two research problems. Firstly, how can we elicit experience narra-
tives efficiently? Longitudinal designs such as the one employed in study 2 are labor
intensive and, consequently, they are often restricted in terms of user population,
product population, and studied time. In chapter 5 we review existing methodologi-
cal approaches for studying temporal changes in user experience and present a novel
survey technique that aims at assisting users in self-reporting their most impactful
experiences with a product.
Secondly, how can we aggregate the idiosyncratic experiences into generalized
knowledge? In chapter 6 we propose a novel technique for the semi-automatic anal-
ysis of experience narratives that combines traditional qualitative coding procedures
(Strauss and Corbin, 1998) with computational approaches for assessing the seman-
tic similarity between documents (Salton et al., 1975).

4.6 Conclusion

This chapter presented two studies that aimed to assess the differences between
initial and prolonged experiences with interactive products.
The first study assessed the ways in which 10 individuals formed overall evalu-
ations of a novel pointing device across two points in the adoption of the product:
during the first week and after four weeks of use. Findings suggested judgments
of the overall goodness of the product to shift from a use-based evaluation dom-
inated by the pragmatic quality of the product, i.e. usefulness and ease-of-use, to
an ownership-based evaluation dominated by aspects of identification, i.e. what the
product expressed about their self-identify in social contexts. Judgments of beauty
seemed to be dominated by perceptions of novelty during initial interactions, but
this effect seemed to disappear after four weeks of use.
The second study followed six individuals through an actual purchase of the
Apple iPhone and inquired into how their expectations and experiences developed
one week before and four weeks after the purchase of the product. The study re-
vealed that the product qualities that provided positive initial experiences were not
very crucial for motivating prolonged use. Product adoption contained three distinct
phases: an initial orientation to the product dominated by the qualities of stimulation
and learnability, a subsequent incorporation of the product in daily routines where
usefulness and long-term usability became more important, and finally, a phase of