I'm working on an algorithm that estimates two parameters of its input data. I have a representative set of samples with the true parameters, to act as a ground truth. As this algorithm uses a threshold that has to be adjusted manually by the user, I was wondering if it could be possible to use my "ground truth" samples to find the best threshold for my training set. How can I express an error metric for two dependant variables, since for each threshold value and sample I'll have two parameters estimated by the algorithm.
I would really appreciate any hint.
Thanks in advance.