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Choi J, O'Malley AJ.Choi J, et al.J R Stat Soc Ser C Appl Stat. 2017 Jan;66(1):159-185. doi: 10.1111/rssc.12158. Epub 2016 Jun 27.J R Stat Soc Ser C Appl Stat. 2017.PMID: 30686843Free PMC article.