Very good question. Author A would still get some reputation gain, due to the way we compute the edit distance. A would gain less reputation than if his contribution survived intact.
Specifically, assume that there is a revision r0, A adds an n-words piece of text making it become r1, and B then rewrites A's contribution, obtaining r2. Due to the way we compute edit distances, we have:
d(r0, r1) = n d(r1, r2) = n/2 d(r0,r2) = n
So the quality of A's contribution is q = (d(r0,r2) - d(r1,r2)) / d(r0,r1) = (n - n/2) / n = 1/2 > 0
and A gets half of the reputation gain it would have gotten, had hes text not been rewritten. The reason d(r1, r2) = n/2 is that our algorithm distinguishes, when giving credit, replacements from insertions / removals. Note that people who insert pure spam have their contribution removed, not rewritten, so even with the above lenient treatment of replacements, spammers do not end up gaining reputation.
When developing the reputation algorithms, we (Bo and I) went over hundreds of revisions which were marked with negative quality, checking that the author really deserved the reputation loss they got by authoring that revision. We tweaked the algorithms as a consequence; the treatment of replacements described above was introduced precisely to give reputation to authors, even in the face of wordsmithing or copy-editing.
Luca
On Mon, Nov 24, 2008 at 7:59 PM, J.L.W.S. The Special One < hildanknight@gmail.com> wrote:
How would the system handle a paragraph full of high quality, well-referenced and well-organised content contributed by an editor A, that is thoroughly copyedited by an editor B? Would editor A be deemed less trustworthy when his prose is thoroughly copyedited?