Excellent service quality and high customer satisfaction is the key issue and challenge for
today’s service industry. Customer perception (satisfaction) and customer expectation (importance)
determines the service quality performance. Questionnaires help service providers to realize their
service quality performance, and the weighted average of customer satisfaction and the associated
variance are commonly used indices reflecting customer expectation and customer perception. To
evaluate, effectively and efficiently, service quality performance, this paper aims to portray customer
expectation and customer satisfaction by assuming that the evaluation scales for expectation and
satisfaction are between 0 and 1. This paper defines a customer satisfaction index and a customer
expectation index based on the two parameters of a beta distribution, and the unbiased estimators for
these two indices are provided. A standardized Service Quality Performance Matrix helps managers
realize the service quality performance for important service elements with respect to the locations of
the satisfaction index and the expectation index on the Service Quality Performance Matrix to
propose adequate service quality improvement plans and strategies.
