TY - JOUR
T1 - Nature versus Nurture
T2 - Investigating the Effects of Measurement Uncertainties in the Assessment of Potential Trends between Planetary and Stellar Properties
AU - Safsten, Emily D.
AU - Dawson, Rebekah I.
N1 - Funding Information:
We thank the referee for the helpful comments on this paper. We thank Angie Wolfgang for helpful discussions. We gratefully acknowledge support from NASA XRP 80NSSC18K0355. This material is based on work supported by the National Aeronautics and Space Administration under grant No. 80NSSC20M0097 issued through the PA Space Grant Consortium. The Center for Exoplanets and Habitable Worlds is supported by the Pennsylvania State University, the Eberly College of Science, and the Pennsylvania Space Grant Consortium. Computations for this research were performed on the Pennsylvania State University’s Institute for Computational and Data Sciences Roar supercomputer. This content is solely the responsibility of the authors and does not necessarily represent the views of the Institute for Computational and Data Sciences. We thank Andrew Polasky and Weinan Chen for input on parallel processing techniques. This research has made use of the NASA Exoplanet Archive, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. This research has made use of data obtained from or tools provided by the portal exoplanet.eu of the Extrasolar Planets Encyclopaedia. We acknowledge the use of the software packages NumPy (Harris et al. ), in performing calculations and generating random numbers; Pandas (McKinney , ), in reading in data files; Matplotlib (Hunter ), in generating plots; and Cython (Behnel et al. ) and PyJulia (Arakaki et al. ), in creating code that runs faster than pure Python.
Publisher Copyright:
© 2022. The Author(s). Published by the American Astronomical Society.
PY - 2022/4/1
Y1 - 2022/4/1
N2 - Correlations between planetary and stellar properties, particularly age, can provide insight on planetary formation and evolution processes. However, the underlying source of such trends can be unclear, and measurement uncertainties and small sample sizes can leave doubt as to whether an observed trend truly exists. We use a Bayesian framework to examine how uncertainties in measured parameters influence the odds ratios of competing hypotheses for the source of an observed trend. We analyze three reported trends from the literature. In each application, while uncertainties do affect the numerical value of the odds ratios, our conclusions remain the same whether or not uncertainties are taken into account: hot Jupiter eccentricities are circularized over time, obliquities of hot Jupiter hosts are driven by stellar temperature, and there is not enough evidence to favor a trend of 2:1 orbital resonances with age over a chance relation. Updated samples for the 2:1 resonance and obliquity cases do not change the original conclusions. Simulated 2:1 resonance data show that sample size may be more important than measurement precision for drawing a firm conclusion. However, if 2:1 resonances get disrupted on a wide range of timescales, an age trend will be inherently difficult to confirm over a chance relation, even with a large sample. For some applications, full incorporation of measurement uncertainties may be too computationally expensive, making it preferable to use the framework without uncertainties and perform additional tests to examine the effects of highly uncertain measurements.
AB - Correlations between planetary and stellar properties, particularly age, can provide insight on planetary formation and evolution processes. However, the underlying source of such trends can be unclear, and measurement uncertainties and small sample sizes can leave doubt as to whether an observed trend truly exists. We use a Bayesian framework to examine how uncertainties in measured parameters influence the odds ratios of competing hypotheses for the source of an observed trend. We analyze three reported trends from the literature. In each application, while uncertainties do affect the numerical value of the odds ratios, our conclusions remain the same whether or not uncertainties are taken into account: hot Jupiter eccentricities are circularized over time, obliquities of hot Jupiter hosts are driven by stellar temperature, and there is not enough evidence to favor a trend of 2:1 orbital resonances with age over a chance relation. Updated samples for the 2:1 resonance and obliquity cases do not change the original conclusions. Simulated 2:1 resonance data show that sample size may be more important than measurement precision for drawing a firm conclusion. However, if 2:1 resonances get disrupted on a wide range of timescales, an age trend will be inherently difficult to confirm over a chance relation, even with a large sample. For some applications, full incorporation of measurement uncertainties may be too computationally expensive, making it preferable to use the framework without uncertainties and perform additional tests to examine the effects of highly uncertain measurements.
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U2 - 10.3847/1538-3881/ac573a
DO - 10.3847/1538-3881/ac573a
M3 - Article
AN - SCOPUS:85128981423
SN - 0004-6256
VL - 163
JO - Astronomical Journal
JF - Astronomical Journal
IS - 4
M1 - 188
ER -