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Choosing input devices for interactive systems that best suit users needs remains a challenge, especially consid- ering the increasing number of devices available. The choice often has to be made through empirical evalua- tions. The most frequently used evaluation task hitherto is target acquisition, a task that can be accurately modeled by Fitts law. However, todays use of computer input devices has gone beyond target acquisition alone. In particular, we often need to perform trajectory-based tasks, such as drawing, writing, and navigation. This paper illustrates how a recently discovered model, the steering law, can be applied as an evaluation paradigm complementary to Fitts law. We tested five commonly used computer input devices in two steering tasks, one linear and one circular. Results showed that subjects performance with the five devices could be generally classified into three groups in the following …