MAP-01-011 HFI Technical Guide - Human Factors Integration ...

Annex 3 – HF Techniques, Methods and Tools• The method is entirely generic and can be used in any domain.• Task decomposition provides a much more detailed description of tasksthan traditional task analysis techniques do.• As the analyst has control over the decomposition categories used,potentially any aspect of a task can be evaluated. In particular, thetechnique could be adapted to assess the cognitive componentsassociated with tasks (goals, decisions, SA).• Potentially extremely exhaustive, if the correct decomposition categoriesare used.• Disadvantages• As the task decomposition is potentially so exhaustive, it is a very timeconsuming technique to apply and analyse. The HTA only serves to add tothe high application time. Furthermore, obtaining information about thetasks (observation, interview etc) creates even more work for the analyst.• Task decomposition can be laborious to perform, involving observations,interviews etc.• The development of decomposition categories would also add further timecosts. For use in command and control military environments, it isapparent that a set of categories would have to be developed.A3.4.4Verbal Protocol AnalysisVerbal Protocol Analysis (VPA) is used to make ‘valid inferences’ from thecontent of discourse (DTC199 - Weber 1990). In other words, VPA is used toderive the processes, cognitive and physical, that an individual uses to perform atask. VPA involves creating a written transcript of operator behaviour as theyperform the task under analysis. The transcript is based upon the operator‘thinking aloud’ as he conducts the task under analysis. VPA has been usedextensively as a means of gaining an insight into the cognitive aspects ofcomplex behaviours.• Advantages• Verbal protocol analysis provides a rich data source.• Protocol analysis is particularly effective when used to analyse sequencesof activities.• Verbalisations can provide a genuine insight into cognitive processes.• Domain experts can provide excellent verbal data.• Verbal protocol analysis has been used extensively in a wide variety ofdomains.May 2006 Page A3-31 Issue 4