A single spherical antenna is capable of measuring the direction and polari
zation of a gravitational wave. It is possible to solve the inverse problem
using only linear algebra even in the presence of noise. The simplicity of
this solution enables one to explore the error on the solution using stand
ard techniques. In this paper we derive the error on the direction and pola
rization measurements of a gravitational wave. We show that the solid angle
error and the uncertainty on the wave amplitude are direction independent.
We also discuss the possibility of determining the polarization amplitudes
with isotropic sensitivity for any given gravitational wave source.