The Optical Luminosity Function of Void Galaxies in the SDSS and ALFALFA
  Surveys
  We measure the r-band galaxy luminosity function (LF) across environments
over the redshift range 0<$z$<0.107 using the SDSS. We divide our sample into
galaxies residing in large scale voids (void galaxies) and those residing in
denser regions (wall galaxies). The best fitting Schechter parameters for void
galaxies are: log$\Phi^*$= -3.40$\pm$0.03 log(Mpc$^{-3}$), $M^*$=
-19.88$\pm$0.05, and $\alpha$=-1.20$\pm$0.02. For wall galaxies, the best
fitting parameters are: log$\Phi^*$=-2.86$\pm$0.02 log(Mpc$^{-3}$),
$M^*$=-20.80$\pm$0.03, and $\alpha$=-1.16$\pm$0.01. We find a shift in the
characteristic magnitude, $M^*$, towards fainter magnitudes for void galaxies
and find no significant difference between the faint-end slopes of the void and
wall galaxy LFs. We investigate how low surface brightness selections effects
can affect the galaxy LF. To attempt to examine a sample of galaxies that is
relatively free of surface brightness selection effects, we compute the optical
galaxy LF of galaxies detected by the blind HI survey, ALFALFA. We find that
the global LF of the ALFALFA sample is not well fit by a Schechter function,
because of the presence of a wide dip in the LF around $M_r$=-18 and an upturn
at fainter magnitudes ($\alpha$~-1.47). We compare the HI selected r-band LF to
various LFs of optically selected populations to determine where the HI
selected optical LF obtains its shape. We find that sample selection plays a
large role in determining the shape of the LF.
