title: Similarity between two signals: looking for simple measure
body: <p>I have 20 signals (time-courses) in group A and 20 signals in group B. I want to find a measure to show that group A is different from group B. For example, I ran xcorr for the signals within each group. But now I need to compare them somehow. I tried to take a maximal amplitude of each xcorr pair, which is sort a measure of maximal similarity. Then I compared all these values between two groups, but there was no difference. What else can I do? I can also compare frequency spectrum, but then I again do not know what frequency bin to take.
  Any suggestions / references are highly appreciated!</p>
  <p>I have about 20 signals in each group. Those are my samples. I do not know a-prirori what might be the difference. Here I bring the 9 sample signals for each group, their auto-correlation and cross-correlation for a subset of signals (group 1 vs. group 1, group 2 vs. group 2, group 1 vs. group 2). I do not see any evident difference. I also do not understand how you propose to compare cross-correlations, what peaks should I take? All the signals were detrended and z-scored.</p>
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