I think a good metric is this: Assuming we independently draw from the observed distribution of achieved karma scores, what is the probability that someone gets at least as much karma as Yvain when she posts as many quotes as Yvain? You can calculate this by iterated convolution. The assumption of total independence heavily favors Yvain, but I am fine with that.

I loaded the actual observed distribution, and calculated this score:

• 0.00008 (12.48 in 54): Rain
• 0.00066 (15.53 in 17): Yvain
• 0.00128 (13.15 in 27): MichaelGR
• 0.00174 (54.00 in 1): michaelkeenan
• 0.00312 (13.29 in 21): RobinZ
• 0.00766 (22.67 in 3): Tesseract
• 0.00836 (18.80 in 5): Unnamed
• 0.01499 (18.25 in 4): sketerpot
• 0.02368 (10.15 in 47): Eliezer_Yudkowsky
• 0.02473 (18.33 in 3): Kyre
• 0.03460 (19.50 in 2): knb
• 0.03831 (15.50 in 4): Lightwave
• 0.04265 (23.00 in 1): Vlad
• 0.04817 (16.00 in 3): Hariant
• 0.05266 (12.86 in 7): Kutta
• 0.05396 (22.00 in 1): DaveInNYC
• 0.06051 (12.57 in 7): wuwei
• 0.06789 (20.00 in 1): CSmith
• 0.07663 (13.50 in 4): Apprentice
• 0.07663 (13.50 in 4): komponisto
• 0.08094 (19.00 in 1): Marcello
• 0.08622 (14.00 in 3): jaimeastorga2000
• 0.08622 (14.00 in 3): MichaelHoward
• 0.09554 (11.38 in 8): billswift
• 0.10009 (18.00 in 1): cata
• 0.11401 (17.00 in 1): MarcTheEngineer
• 0.12449 (8.77 in 81): RichardKennaway
• 0.12763 (12.00 in 4): SilasBarta
• 0.13055 (16.00 in 1): CaptainOblivious2
• 0.13055 (16.00 in 1): Tyrrell_McAllister
• 0.13092 (13.50 in 2): JamesAndrix
• 0.13828 (12.33 in 3): Randaly
• 0.14534 (15.00 in 1): Automaton
• 0.14534 (15.00 in 1): loqi
• 0.14534 (15.00 in 1): Nisan
• 0.14534 (15.00 in 1): Patrick
• 0.14534 (15.00 in 1): teageegeepea
• 0.14695 (13.00 in 2): BenAlbahari
• 0.15183 (10.83 in 6): DSimon