Event-Based GUI Testing and Reliability Assessment Techniques -- An Experimental Insight and Preliminary Results

It is widely accepted that graphical user interfaces (GUIs) highly affect - positive or negative - the quality and reliability of human-machine systems. In spite of this fact, quantitative assessment of the reliability of GUIs is a relatively young research field. Existing software reliability assessment techniques attempt to statistically describe the software testing process and to determine and thus predict the reliability of the system under consideration (SUC). These techniques model the reliability of the SUC based on particular assumptions and preconditions on probability distribution of cumulative number of failures, failure data observed, and form of the failure intensity function, etc. We expect that the methods used for modeling a GUI and related frameworks used for testing it also affect the factors mentioned above, especially failure data to be observed and prerequisites to be met. Thus, the quality of the reliability assessment process, and ultimately also the reliability of the GUI, depends on the methods used for modeling and testing the SUC. This paper attempts to gain some experimental insight into this problem. GUI testing frameworks based on event sequence graphs and event flow graphs were chosen as examples. A case study drawn from a large commercial web-based system is used to carry out the experiments and discuss the results.