  Human figures have been animated using a variety of geometric models
including stick figures, polygonal models, and NURBS-based models with muscles,
flexible skin, or clothing. This paper reports on experimental results
indicating that a viewer's perception of motion characteristics is affected by
the geometric model used for rendering. Subjects were shown a series of paired
motion sequences and asked if the two motions in each pair were the same or
different. The motion sequences in each pair were rendered using the same
geometric model. For the three types of motion variation tested, sensitivity
scores indicate that subjects were better able to observe changes with the
polygonal model than they were with the stick figure model.
