Perceptual independence of whole length, partial length, and hand positionin wielding a rod

Previous investigations of dynamic touch have shown that, in wielding an oc cluded rod, the nonvisible perceptions of total rod length, hand position, and fractional rod length above or below the hand are different functions o f the eigenvalues and eigenvectors of the inertia tensor. The implication t hat the 3 perceptions are independent covariants of the inertia tensor of a wielded object was tested with the complete identification experimental pr ocedure using the statistical prescriptions of F. G. Ashby and J. T. Townse nd (1986). The confirmed independence is discussed in the context of the ge neralized psychophysical or perception-information hypothesis.