  The fact that the number of users of open source software (OSS) is
practically un-limited and that ultimately the software quality is determined
by end users experience, makes the usability an even more critical quality
attribute than it is for proprietary software. With the sharp increase in use
of open source projects by both individuals and organizations, the level of
usability and related issues must be addressed more seriously. The research
model of this empirical investigation studies and establishes the relationship
between the key usability factors from contributors perspective and OSS
usability. A data set of 78 OSS contributors that includes architects,
designers, developers, testers and users from 22 open source projects of varied
size has been used to study the research model. The results of this study
provide empirical evidence by indicating that the highlighted key factors play
a significant role in improving OSS usability.
