Improved Requirements through the Use of Scenarios and Usability Tests on Early Prototypes


There is no generally accepted way of making a requirements specification. Recommendations like the IEEE Guide to Software Requirements Specifications (IEEE Std. 830) and A.M. Davis' book (Software Requirements, Analysis and Specification) are definitely helpful, but most developers have great troubles following them.

  • What should be included and what not?
  • How can you formulate "what" without describing "how"?
Through the analysis of error reports from software development projects, we have found that problems related to requirements are the major cause for bugs. We have analysed these type of bugs in detail in order to find and introduce effective prevention techniques for requirements problems in our development process. The analysis showed that usability issues dominate (64%).

We have found that the most effective way to improve the requirements engineering process is to define and describe common work situations (scenarios) for the product to be developed, and validate these work situations through usability tests on very early prototypes.

This two day workshop should be held when your project team has been formed, very early in the requirements phase. E.g. the workshop could be combined with other team building activities. Your team will work with these techniques based on their own knowledge about the initial requirements for the product.

The workshop will give your project team practical, workable knowledge on:

  • How to describe work situations (scenarios) and define the users' tasks.
  • How to validate the work situations through usability tests on early prototypes.
  • Important usability principles.
The workshop will give your project team the necessary skills in these techniques so that your requirements engineering process is improved dramatically. This will not only reduce the number of problems later during development and after release. More important, it will improve the resulting product, increase the fulfilment of customer needs, and therefore the sales of your products.

The agenda for the workshop is:

  1. The background: How the techniques were selected and validated
  2. Scenario technique
  3. Group work: Scenarios
  4. Prototyping
  5. Group work: Design a paper mock-up
  6. Usability testing techniques
  7. Group work: Perform a usability test
  8. Experiences from practical use of the techniques

More information

The background for this workshop was a Process Improvement Experiment (PRIDE) funded by EU under the ESSI programme. ESSI (European System and Software Initiative) aims at improving Software Best Practice in Europe. The final report can be downloaded from here: Finalrp3.doc.
The results of the experiment were in a shorter form presented at e.g. QWE'98 under the title: "Improved Requirements Engineering Based on Defect Analysis". You can download from here the paper and viewgraphs.
After the completion of the experiment, we have gathered large scale experiences using the techniques including their diffusion and adoption in the organisation. You can download the full report (in Danish): Rapport fra forbedringsaktivitet: Kravspecifikationer.
All of the experiences in the reports above are included in the workshop.

About the instructor

Otto Vinter is a software engineering mentor specialising in software process improvements. He is on the programme committee of several international conferences, performs mentoring activities for clients, and is an expert evaluator on the framework programmes of the CEC.
The above work was performed while he was responsible for software process improvements projects at Brüel & Kjær. He has also been active in defining software engineering standards, procedures, and methods to be employed at Brüel & Kjær.
He has managed software development projects for 30 years. He holds a Masters Degree in Computer Science from the Danish Technical University (1968).


Email: mail@ottovinter.dk
My English home page
Min danske hjemmeside

Last modified: 2008-10-21