Ron now concedes that we are on shaky ground in claiming that our tests' ceilings are appreciably above IQ 180 (personal communication).
I want to make it clear that I do not maintain that the relationship of scores is linear, only that we don't have sufficient data to draw any better conclusions.
One difficulty with attempting to draw conclusions about very high scores is that there are very few data points to work with. Surely some testees have much higher IQ's, but the data doesn't permit us to say with confidence which ones, nor how high their IQ's might be, with an acceptable degree of confidence.
See my remarks [in this issue], excerpted from my letter in Noesis #135, regarding the question of ceiling bumping.