Just a quick update, some weeks ago I rapidly coded a prototype of this idea of an estimation game, in which you have to guess different facts and the app gives an “accuracy” score. Turned out that the problem of measuring accuracy in guessing is an interesting one and could be solved in many ways. My approach was
score = min(guess,realValue)/max(guess,realValue)
To me this metric is interesting because indicates an “order of magnitude” error, that is if our guess is double or half the actual value, the score is the same.
Of course this formula is only good for positive values, and is not that good if we’re trying to guess bounded values, like if I ask to guess the year of birth of someone: you already have some very clear bounds and you will easily get a score of 95% or so.
The (very basic, only mobile) app is here:
I didn’t bother to fix the style for desktop PC – just mobile. Here’s a screenshot: