We survey our members on a regular basis on various topics, but with always the same question (basically, do you like it? yes or no), and we classify them based on what is replied, and how many participated in the survey.
When we send the email, we would like to be able to know at what point in time we can estimate that the final result (how many people will fill, what % of yes) is likely to be the one we have now.
We did process the previous surveys, and we can see a pattern where after 6 or 12 hours, the result is similar to the final one (ie when we wait more than a week after the mailing). Obviously, a survey sent friday at 8pm takes longer to reach a conclusive stage than the ones sent on tue at 9am. They are other factors too, for instance if our mail provider experienced delay delivering, then of course we need to wait longer.
Is there a way to know how long to wait (3, 6, 12... hours?) before we get a solid prediction of the result?
Is there an algorithm that can predict the result at any point in time and give an estimate on how likely the estimate is correct (p value like)?