|dc.description.abstract||It has been suggested 'expert systems' might have a significant role in the future through
enabling many more people to access human experts. It is, therefore, important to
understand how potential users interact with these computer systems. This study
investigates the effect of extension agents' attitudes towards the features and use of an
example expert system for rice disease diagnosis and management(POSOP). It also
considers the effect of extension agents' personality traits and intelligence on their attitudes
towards its use, and the agents' perception of control over using it. Answers to these
questions lead to developing better systems and to increasing their adoption.
Using structural equation modelling, two models - the extension agents' perceived
usefulness of POSOP, and their attitude towards the use of POSOP, were developed
(Models ATU and ATP). Two of POSOP's features (its value as a decision support tool,
and its user interface), two personality traits (Openness (0) and Extraversion (E)), and the
agents' intelligence, proved to be significant, and were evaluated.
The agents' attitude towards POSOP's value had a substantial impact on their perceived
usefulness and their attitude towards using it, and thus their intention to use POSOP. Their
attitude towards POSOP's user interface also had an impact on their attitude towards its
perceived usefulness, but had no impact on their attitude towards using it. However, the
user interface did contribute to its value.
In Model ATU, neither Openness (0) nor Extraversion (E) had an impact on the agents'
perceived usefulness indicating POSOP was considered useful regardless of the agents'
personality background. However, Extraversion (E) had a negative impact on their intention to use POSOP in Model ATP indicating that 'introverted' agents had a clear
intention to use POSOP relative to the 'extroverted' agents.
Extension agents' intelligence, in terms of their GPA, had neither an impact on their
attitude, nor their subjective norm (expectation of 'others' beliefs), to the use of POSOP. It
also had no association with any of the variables in both models.
Both models explain and predict that it is likely that the agents will use POSOP. However,
the availability of computers, particularly their capacity, are likely to impede its use.
Although the agents believed using POSOP would not be difficult, they still believed
training would be beneficial.
To be a useful decision support tool, the expert system's value and user interface as well as
its usefulness and ease of use, are all crucially important to the preliminary acceptance of a
system. Most importantly, the users' problems and needs should be assessed and taken into
account as a first priority in developing an expert system. Furthermore, the users should be
involved in the system development.
The results emphasise that the use of an expert system is not only determined by the
system's value and its user interface, but also the agents' perceived usefulness, and their
attitude towards using it. In addition, the agents' perception of control over using it is also
a significant factor. The results suggested improvements to the system's value and its user
interface would increase its potential use, and also providing suitable computers, coupled
with training, would encourage its use.||en