Robust sampling for weak lensing and clustering analyses with the Dark Energy Survey

Lemos, P.; Weaverdyck, N.; Rollins, R. P.; Muir, J.; Ferté, A.; Liddle, A. R.; Campos, A.; Huterer, D.; Raveri, M.; Zuntz, J.; Di Valentino, E.; Fang, X.; Hartley, W. G.; Aguena, M.; Allam, S.; Annis, J.; Bertin, E.; Bocquet, S.; Brooks, D.; Burke, D. L.; Carnero Rosell, A.; Carrasco Kind, M.; Carretero, J.; Castander, F. J.; Choi, A.; Costanzi, M.; Crocce, M.; da Costa, L. N.; Pereira, M. E. S.; Dietrich, J. P.; Everett, S.; Ferrero, I.; Frieman, J.; García-Bellido, J.; Gatti, M.; Gaztanaga, E.; Gerdes, D. W.; Gruen, D.; Gruendl, R. A.; Gschwend, J.; Gutierrez, G.; Hinton, S. R.; Hollowood, D. L.; Honscheid, K.; James, D. J.; Kuehn, K.; Kuropatkin, N.; Lima, M.; March, M.; Melchior, P.; Menanteau, F.; Miquel, R.; Morgan, R.; Palmese, A.; Paz-Chinchón, F.; Pieres, A.; Malagón, A. A. Plazas; Porredon, A.; Sanchez, E.; Scarpine, V.; Schubnell, M.; Serrano, S.; Sevilla-Noarbe, I.; Smith, M.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thomas, D.; To, C.; Varga, T. N.; Weller, J.; DES Collaboration
Bibliographical reference

Monthly Notices of the Royal Astronomical Society

Advertised on:
5
2023
Number of authors
72
IAC number of authors
1
Citations
34
Refereed citations
21
Description
Recent cosmological analyses rely on the ability to accurately sample from high-dimensional posterior distributions. A variety of algorithms have been applied in the field, but justification of the particular sampler choice and settings is often lacking. Here, we investigate three such samplers to motivate and validate the algorithm and settings used for the Dark Energy Survey (DES) analyses of the first 3 yr (Y3) of data from combined measurements of weak lensing and galaxy clustering. We employ the full DES Year 1 likelihood alongside a much faster approximate likelihood, which enables us to assess the outcomes from each sampler choice and demonstrate the robustness of our full results. We find that the ellipsoidal nested sampling algorithm MULTINEST reports inconsistent estimates of the Bayesian evidence and somewhat narrower parameter credible intervals than the sliced nested sampling implemented in POLYCHORD. We compare the findings from MULTINEST and POLYCHORD with parameter inference from the Metropolis-Hastings algorithm, finding good agreement. We determine that POLYCHORD provides a good balance of speed and robustness for posterior and evidence estimation, and recommend different settings for testing purposes and final chains for analyses with DES Y3 data. Our methodology can readily be reproduced to obtain suitable sampler settings for future surveys.
Related projects
 The Invisible Scaffolding of Space
Cosmology with Large Scale Structure Probes
The Cosmic Microwave Background (CMB) contains the statistical information about the early seeds of the structure formation in our Universe. Its natural counterpart in the local universe is the distribution of galaxies that arises as a result of gravitational growth of those primordial and small density fluctuations. The characterization of the
FRANCISCO SHU
KITAURA JOYANES