Came across this on PLOS ONE. Seems decently done, interesting for those who race and/or watch racing. You can download the pdf with the button to the right of the title. Bottom line is that each discipline has its own outcomes, but SG and DH cluster a bit while GS is on its own, and surprisingly, DH speed isn't effected by terrain. The actual speeds are interesting, too, for those endless arguments here about how fast we ski.