First, Thanks you for releasing an audio competition !
I was looking into the data, and It seems to be a multi class problem, but when I look the example in evaluation, it seems the sum of the probability are above 1.0. Does that mean this competition is finally a multi label task ? Can we have multiple label for one audio sample ?
Each audio sample has ONE keyword as the label. Submission example shows format: floats for probabilities. Note there are also only three classes in that example. Sorry if it's misleading - this is still just a multi-class problem.
Should the probabilities add up to 1 or more than 1?
If they add up to more than one they'll be scaled during scoring if I remember correctly. You definitely won't get an error if they don't sum exactly to one.