PHAT

Rix, Julianne Dalcanton (UW), and I spent a morning in the garden discussing the high-level data-analysis plan (or maybe inference plan) for Dalcanton's PHAT project. This project is imaging a large part of Andromeda and the inference is about the ages, masses, and initial mass functions of young stellar clusters. Among other things we discussed the difference between a model that assumes a flat age distribution, and a model that insists on a flat age distribution, and the difficulty of making the latter within Bayesian inference. Indeed, this was what was hard initially about Bovy and my Solar System (or orbital roulette) project.