  This paper deals with errors in using spreadsheets and analysis of automatic
recording of user interaction with spreadsheets. After a review of literature
devoted to spreadsheet errors, we advocate the importance of going from error
detection to interaction behaviour analysis. We explain how we analyze screen
captures and give the main results we have obtained using this specific
methodology with secondary school students (N=24). Transcription provides
general characteristics: time, sequence of performed tasks, unsuccessful
attempts and user preferences. Analysis reveals preferred modes of actions
(toolbar buttons or menu commands), ways of writing formulas, and typical
approaches in searching for solutions. Time, rhythm and density appear to be
promising indicators. We think such an approach (to analyze screen captures)
could be used with more advanced spreadsheet users.
