  The local void model has lately attracted considerable attention since it can
explain the present apparent accelerated expansion of the universe without
introducing dark energy. However, in order to justify this model as an
alternative cosmological model to the standard $\Lambda$CDM model (FLRW
universe plus dark energy), one has to test the model by various observations,
such as CMB temperature anisotropy, other than the distance-redshift relation
of SNIa. For this purpose, we derive some analytic formulae that can be used to
rigorously compare consequences of this model with observations of CMB
anisotropy and to place constraints on the position of observers in the void
model.
