difference in shape of line graphs

[paulinenj]

Hi,

I have 2 set of four data points per individual. I am trying to compare the difference between the shape of two profiles, rather than the actual scores on each measure. I need one number to represent the difference.

My thinking is to take the difference between A and B, A and C, A and D...then the difference between B and C, B and D, etc. ....and I'm stuck from there. Basically I need to know if there is an effective way of doing this, rather than using my own lack of expertise.

Thanks,

Polly:wave:

[JohnM]

Trying to use numerical descriptors to boil down curvature, slope, shape, etc. can get extremely complicated, so at first I would try a generic descriptive approach that just identifies the curve based on slope (upward, downward, etc.) and convex / concave.

What is it about the difference in shapes that is important?