  Only certain galaxies are included in surveys: those bright and large enough
to be detectable as extended sources. Because gravitational lensing can make
galaxies appear both brighter and larger, the presence of foreground
inhomogeneities can scatter galaxies across not only magnitude cuts but also
size cuts, changing the statistical properties of the resulting catalog. Here
we explore this size bias, and how it combines with magnification bias to
affect galaxy statistics. We demonstrate that photometric galaxy samples from
current and upcoming surveys can be even more affected by size bias than by
magnification bias.
