title: Comment.
authors.affiliation: Department of Statistics, North Carolina State University, Raleigh, NC, USA.
authors.forename: Qian
authors.initials: Q
authors.lastname: Guan
authors.affiliation: Department of Statistics, North Carolina State University, Raleigh, NC, USA.
authors.forename: Eric B
authors.initials: EB
authors.lastname: Laber
authors.affiliation: Department of Statistics, North Carolina State University, Raleigh, NC, USA.
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Reich