parameter estimation for a crystalliser model

Hi, im trying to get parameters for two equations which are part of a population balance model. i have two sets of experimental data to fit the model too. however one data set(concentration is a vector and the other (mean size)is a scaler. how would i formulate the objective function for fminsearch? at the moment im just lumping experimetal data and simulated data and minimising the difference in the sums.doesnt work

[Andrew Newell]

You need to supply some more information. What are your two equations calculating? What are the parameters? Is the vector of concentrations a set of measurements of the same concentration or different concentrations?