  We examine the problem of estimating the mass range corresponding to the
observed red supergiant (RSG) progenitors of Type IIP supernovae. Using Monte
Carlo simulations designed to reproduce the properties of the observations, we
find that the approach of Davies & Beasor (2018) significantly overestimates
the maximum mass, yielding an upper limit of Mh/Msun=20.5+/-2.6 for an input
population with Mh/Msun=18. Our preferred Bayesian approach does better, with
Mh/Msun=18.6+/-2.1 for the same input populations, but also tends to
overestimate Mh. For the actual progenitor sample and a Salpeter initial mass
function we find Mh/Msun=19.01-2.04+4.04 for the Eldridge et al. (2004)
mass-luminosity relation used by Smartt et al. (2009) and Davies & Beasor
(2018), and Mh/Msun=21.28_-2.28+4.52 for the Sukhbold et al. (2018)
mass-luminosity relation. Based on the Monte Carlo simulations, we estimate
that these are overestimated by 3.3+/-0.8Mh. The red supergiant problem
remains.
