1. A method for calibrating a probe apparatus which provides three-dimensional position and orientation data to a computer system, said probe apparatus including a probe coupled to a mechanical linkage assembly including a plurality of joints, said mechanical linkage assembly being supported by a support base, wherein said probe is moveable within a selected volume, and wherein sensors coupled to said mechanical linkage assembly are operative to sense joint angles related to a position and orientation of said probe and provide joint angle data to said computer system, the method comprising: (a) positioning said probe such that a known point on said probe is located at an arbitrary location within said selected volume with respect to said support base; (b) varying an orientation of said probe to move a plurality of joints of said mechanical linkage assembly while maintaining said known point on said probe at said arbitrary location; (c) sampling sets of data at a plurality of orientations of said probe as said orientation of said probe is varied about said arbitrary location, said sets of data being provided by said sensors and describing different configurations of angles of said joints; (d) determining a set of spatial coordinates for said known point on said probe at each of said plurality of orientations of said probe; (e) determining a plurality of error, values each error value being between said set of said spatial coordinates determined for each of said plurality of said orientations of said probe and at least one other set of said spatial coordinates; and (f) increasing the accuracy of position and orientation data provided by said probe apparatus by determining calibration parameters based on said error values, said calibration parameters being used when determining said position and orientation of said probe in normal usage.