The predictability of commands in a spreadsheet program
Norman S. Guadagno, David M. Lane, Richard R. Batsell, H. Albert Napier · Interacting with Computers · 1990
The ability to predict users' commands in Lotus 1-2-3 was investigated. Keystroke data was collected from four subjects in their normal work environment, with over 2700 commands being analysed. The data was used to construct transitional probability matrices that were then used to predict commands based on their immediate predecessors. Approximately half of the users' commands were correctly predicted in this manner. Also of interest was how often the users' commands would be either the most likely or the second most likely command given the previous commands. When the previous two commands were used to derive two predictions, the probability that the users' next command would be one of the two predicted commands was 0.81. The average probability of command repetition was 0.33. It was concluded that users appear to be extremely predictable in the Lotus 1-2-3 environment, and this predictability could serve as the foundation for an interface that aids the user by providing easy access to the next most likely command to be issued and by adapting the probabilities of command use over time.