Well we do have that for the "weighted dice" from the start of patch 4.
The data Niara posted is concerning enough that I'd want to see this studied more with a larger sample size. It's also DEFINITELY enough to not be dismissed out of hand as some are apparently wont to do. What it ISN'T is enough to draw any conclusions. I'd want a sample size of 1000+ before making a conclusion on something like this.
Unfortunately I have no idea how to efficiently collect this data short of reloading right before a dice role 1000 times which obviously no one is gonna do.
The good news is that the patch 4 "weighted dice" had a nice random distribution. (they were weighted to reduce streaks, the base RNG had a propensity to trend/streak).
The bad news is that a hot-fix replaced that set of "weighted dice" with dice that are allowed to streak on high rolls.
So now we get to choose between streaky dice and rigged dice.
Here is a post from a thread on the base-game RNG links are great.