GR translation: you’d be amazed at the frequency with this one

[Mike Jing]

V32.5-19, P32.23-38   “Well. Recall Zipf’s Principle of Least Effort: if we
plot the frequency of a word P sub n against its rank-order n on
logarithmic axes,” babbling into her silence, even her bewilderment
graceful, “we should of course get something like a straight line . . .
however we’ve data that suggest the curves for certain—conditions, well
they’re actually quite different—schizophrenics for example tend to run a
bit flatter in the upper part then progressively steeper—a sort of bow
shape . . . I think with this chap, this Roland, that we’re on to a
classical paranoiac—”
       Ha. That’s a word she knows. “Thought I saw you brighten up there
when he said ‘turned against.’ ”
       “‘Against,’ ‘opposite,’ yes you’d be amazed at the frequency with
this one.”
       “What’s the most frequent word?” asks Jessica. “Your number one.”
       “The same as it’s always been at these affairs,” replies the
statistician, as if everyone knew: “death.”

What does "this one" refer to here?