Quality Evaluation Models - High Level Models and Methodologies for Information Systems - page 105

IDT-based models have been considerably successful in research, particularly in
the prediction of social response regarding speci c products. The ability to predict

the social stance that a product will generate has often sparked the interest of the
research community in this framework (Yu and Wang 2007 ) (Fig. 6.9 ).
It has also been noted by some researchers that IDT is very complementary to
the TAM and both can be combined into a single framework. The most common
conclusion in this regard is that compatibility directly in uences perceived use-

fulness and behavioral intention to use, the two key aspects of the TAM (Tung et al.
2008 ).

6.9 Expectation Discon rmation Theory (EDT)

-

The expectation discon rmation theory (EDT), also described as expectation -

- -

con rmation theory (ECT), is associated with changes in users ' behavior. Origi-

nally developed in the fields of marketing and consumer behavior research, it

emerged as a methodology to explain the reasons why users

' actions change

throughout time, and how that change is processed.
The main argument in the expectation rmation model (EDM) is that user

satisfaction is originated by their assessment of the divergence between the
expectations they had for a particular service or product before they acquired it, and
the opinion they have on its quality after it has been purchased (Wang and Chang
2013 ). Discon

- discon

rmation is determined at the moment the user has contact and
experience with the product or service. The theory asserts that satisfaction is cor-
related with the direction of the discon

rmation, as users will be satis ed if there is

positive discon rmation (the product was better than expected), and they will be

dissatis rmation (the product was worse than

expected) (Venkatesh and Goyal 2010 ) (Fig. 6.10 ).
We can observe that in the EDT there are three fundamental variables at play:
expectations, which consist of the beliefs the user has regarding use of the product
prior to actually using it; performance, which is the user

ed if there is negative discon

is perception of how the
product performed and whether it achieved its goals; and discon

'

rmation, which is
a subjective comparison that the user will make after using the product, between
how it performed and how he/she expected it to perform in stage 1 (Lankton and
McKnight 2012 ).
IS researchers have adopted the basics of this conceptual model to assert user
satisfaction with IT or IS (Bhattacherjee 2001 ), focusing on the threefold principle
that users will first form expectations about usage, which will combine with per-

formance in a second stage, and in uence the outcome (decision to continue or not

continue usage) in the third stage.
This model is thus able to distinguish the attitude of the user in the preusage and
post-usage periods. Users

'

expectations are the opinions they have about a certain
technology prior to its adoption, consisting in the user

'

s viewpoint of the possibilities
of that technology ' s performance, inferred by some of its traits. The performance