Finding the closest match for data.

Good day, here I've plotted a power, frequency vs time domain of an audio signal.

I have the power, frequency and time values requered to plot this graph. I want to compare words to one another and comput the closest match. I'm thinking of using the mean square error (MSE) using the immse() function, however I'm not sure if that will give me the result I require. If I make a nx3 matrix (with n being many numbers) using horzcat(p,t,f) function to concatenate the power, time and frequency; will I be able to obtain an accurate difference using the immse() function to compare 2 arrays of size nx3? Or would a different approuch be needed to compare them and obtain more accurate results? Thanks in advance!