Astronomical catalogue matching as a mixture model problem
David Rohde, Marcus Gallagher, Michael J. Drinkwater · AIP conference proceedings · 2012
Astronomical telescopes increasingly operate in surveymode sweeping the sky systematically and producing highly processed data products such as astronomical catalogues which are lists of objects with positional information and other measurements usually including flux in a particular band. An important problem in electronic astronomy is the appropriate way to combine information from different catalogues produced by different telescopes. A key problem in combining this information is to establish different observations of the same object in the two catalogues i.e. the problem of catalogue matching. Positional information is not always sufficient in establishing matches reliably in these cases additional information from the non-positional measurements may also be used. This non-positional information is often scientifically interesting and its inter-catalogue properties may be the main object of study. In previous studies it is argued that while models of non-positional properties may assist in catalogue matching if these properties are scientifically interesting then the conclusions drawn from the analysis may be distorted by using this non-positional information. In this paper it is demonstrated that by employing a predictive Bayesian formalism it is possible to use all available information to assist in obtaining the most reliable matches and still obtain undistorted conclusions. Distortions are avoided because predictive distributions are computed where all the configurations of matches are marginalized over, rather than other approaches which choose a single most likely configuration of matches.