I'm confident by now that conditional on my paraphrase being true to the original, Dr. Yagami's statistics don't make any sense. But, like you say, it's possible that I missed something. If someone were willing to take a look at the original text with me, we could probably settle that.
Go zebras! Bevtvany grkg erzbirq nf vg unf freirq vgf checbfr.