Milliseconds matter: an introduction to microstrategies and to their use in describing and predicting interactive behavior.

Interactive behavior is constrained by the design of the artifacts available (e.g., a mouse and button) as well as by the ways in which elementary cognitive, perceptual, and motor operations can be combined. Any 2 basic activities, for example, (a) moving to and (b) clicking on a button, can be combined to yield a limited number of microstrategies. The results of an experimental study suggest that alternative microstrategies can be deployed that shave milliseconds from routine interactive behavior. Data from a usability study are used to explore the potential of microstrategies for (a) bracketing the range of individual performance, (b) profiling individual differences, and (c) diagnosing mismatches between expected and obtained performance. These 2 studies support the arguments that the microstrategies deployed can be sensitive to small features of an interface and that task analyses at the millisecond level can inform design.