``. . . it is clearly seen that bidding on Sunday gives much more ROI compared to other days.''
Like with the econometrics paper about the stock market and Mondays and Tuesdays, this will probably change when Utopian upvotes this post and people see it and it becomes more widely held knowledge. If people know there's money on the table and know where is this table there's very soon no money on the table. Feedback. Stir the barrel and lo! gone is the barrel.
;)
As a final word, I really would like to see if Hawthorne Effect ( observation changes behavior) will work on this analysis. Just because we have determined a "stable timeframe" and "max ROI date" can change the voting behavior of people and a new study would be required.I will keep on analyzing Sundays. This is what I am clearly expecting @Tibra.
To me it is too much resembling the fluid flow, starting laminar and getting turbulant..