Sarah Bridle (UCL) and Marshall called me by Skype (tm) this morning (my time) to discuss Phil and my crazy ideas about inferring the mass distribution and the cosmological parameters from weak-lensing data. Instead, we got sidetracked onto clustering measurements, with me making the pitch that we might be sacrificing signal-to-noise on the baryon acoustic feature by fitting models at the point-estimated (pair counts in separation bins) two-point correlation functions. That is, no large-scale structure project ever writes down a likelihood function for the galaxy positions.
At lunch, Fergus showed me his new and improved models for Oppenheimer's coronograph data. He factorizes the data matrix into principal components, and then finds that he can't fit the data well near the companion (exoplanet) locations with the dominant principal components. Furthermore, he finds that if he fits the data as a mixture of (empirical, data-driven) speckle model for the residual star light plus (heuristic, theory-driven) point-source model for the companion light, he does a great job of separating the components and thereby photometering the companion. Beautiful stuff and music to my ears, methodologically.
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