The mlt package implements maximum likelihood estimation in conditional transformation models as introduced by Hothorn et al. (2018).
An introduction to the package is available in the mlt package
vignette from package mlt.docreg (Hothorn, 2018).
A short talk on most likely transformations is available from https://channel9.msdn.com/Events/useR-international-R-User-conference/useR2016/Most-Likely-Transformations.
Torsten Hothorn, Lisa Moest, Peter Buehlmann (2018), Most Likely Transformations, Scandinavian Journal of Statistics, 45(1), 110--134, 10.1111/sjos.12291.
Torsten Hothorn (2018), Most Likely Transformations: The mlt Package, Journal of Statistical Software, forthcoming. URL: https://cran.r-project.org/package=mlt.docreg.