Imperial College London
Portrait Picture

Professor David van Dyk

Faculty of Natural Sciences, Department of Mathematics

Chair in Statistics
 
 
 
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Contact

 

+44 (0)20 7594 8574d.van-dyk Website

 
 
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Assistant

 

Mr David Whittaker +44 (0)20 7594 8481

 
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Location

 

539Huxley BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Si:2017:mnras/stx765,
author = {Si, S and van, Dyk D and von, Hippel T and Robinson, E and Webster, A and Stenning, D},
doi = {mnras/stx765},
journal = {Monthly Notices of the Royal Astronomical Society},
pages = {4374--4388},
title = {A hierarchical model for the ages of Galactic halo white dwarfs},
url = {http://dx.doi.org/10.1093/mnras/stx765},
volume = {468},
year = {2017}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - In astrophysics, we often aim to estimate one or more parameters for each member object in a population and study the distribution of the fitted parameters across the population. In this paper, we develop novel methods that allow us to take advantage of existing software designed for such case-by-case analyses to simultaneously fit parameters of both the individual objects and the parameters that quantify their distribution across the population. Our methods are based on Bayesian hierarchical modelling that is known to produce parameter estimators for the individual objects that are on average closer to their true values than estimators based on case-by-case analyses. We verify this in the context of estimating ages of Galactic halo white dwarfs (WDs) via a series of simulation studies. Finally, we deploy our new techniques on optical and near-infrared photometry of 10 candidate halo WDs to obtain estimates of their ages along with an estimate of the mean age of Galactic halo WDs of12.11+0.85−0.86Gyr. Although this sample is small, our technique lays the ground work for large-scale studies using data from the Gaia mission.
AU  - Si,S
AU  - van,Dyk D
AU  - von,Hippel T
AU  - Robinson,E
AU  - Webster,A
AU  - Stenning,D
DO  - mnras/stx765
EP  - 4388
PY  - 2017///
SN  - 1365-2966
SP  - 4374
TI  - A hierarchical model for the ages of Galactic halo white dwarfs
T2  - Monthly Notices of the Royal Astronomical Society
UR  - http://dx.doi.org/10.1093/mnras/stx765
UR  - http://hdl.handle.net/10044/1/46138
VL  - 468
ER  -
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