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arXiv · 1905.04593

Accounting for selection bias using simulations: A general method and an application to millimeter-wavelength surveys

Megan B. Gralla·Tobias A. Marriage
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Abstract

We have developed a new Bayesian method to correct the flux densities of astronomical sources. The hybrid method combines a simulated likelihood to model survey selection together with an analytic source-count-based prior. The simulated likelihood captures the effect of complicated selection methods, such as multi-frequency filtering or imposed restrictions on recovered sample properties (e.g., color cuts). Simulations are also able to capture unanticipated sources of uncertainty. In this way, the method enables a broader application of Bayesian techniques. Use of an analytic prior allows variation of assumed source count models without re-simulating the likelihood. We present the method along with a detailed description of an application to real survey data from the Atacama Cosmology Telescope.

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Megan B. Gralla, Tobias A. Marriage. 2020-02-23. Accounting for selection bias using simulations: A general method and an application to millimeter-wavelength surveys. https://doi.org/10.3847/1538-4357%2Fab7916

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