I'm new to math, Matlab, stats, etc... Anyways, I'm trying to fit some data points to a curve, and the equation Matlab spits out is quite inaccurate even though Rsquared is 0.97. Tweaking the degrees of the polynomial doesn't help and from looking at the points, a degree higher than 2 isn't representative of the data. The equation I have is so inaccurate that I don't trust it at all. So, now I'm stuck and don't know what the next step is, except trial and error, i.e. adding and subtracting terms from the equation until I get a regression that I trust more. Is this the right way to go about it? What are some obvious next steps? I've thought about breaking the data points into different groups and finding a regression for each group, then linking the group of equations together. Is this wrong?