I knew I had seen this before but couldn't previously remember where.
https://github.com/lme4/lme4/issues/441 ... I initially fixed with
gsub(), but (pushed by Martin Maechler to do better) I eventually
fixed it by storing the original names of the model frame (without
backticks) as an attribute fo
Thanks to Bill Dunlap for the clarification. On follow-up it turns out that this will be
an issue for many if not most of the routines in the survival package: a lot of them look
at the terms structure and make use of the dimnames of attr(terms, 'factors'), which also
keeps the unneeded backquo
