Using Georgia State University's CHARA Array interferometer, we measured
angular diameters for 25 giant stars, six of which host exoplanets. The
combination of these measurements and Hipparcos parallaxes produce physical
linear radii for the sample. Except for two outliers, our values match angular
diameters and physical radii estimated using photometric methods to within the
associated errors with the advantage that our uncertainties are significantly
lower. We also calculated the effective temperatures for the stars using the
newly-measured diameters. Our values do not match those derived from
spectroscopic observations as well, perhaps due to the inherent properties of
the methods used or because of a missing source of extinction in the stellar
models that would affect the spectroscopic temperatures