Origin Ver. and Service Release (Select Help-->About Origin): Operating System:
Hey,
Using origin 2020. I will be very grateful if anyone could help me, please!
So ALL of my experiments basically rely on me comparing exponential curves for different experiments (concentration vs time). Anyway, I've never had a problem using the exponential functions before but I'm getting some really not-okay graphs.
I have tried playing around with -type of exp. curve I am fitting, the number of iterations I allow Origin to run through (less seems to make it better, but it's still a poor fit.
The crucial element is that I get an equation in the form y = y0 + A*exp(R0*x) for my line.
It's not like my data is ridiculous, I can draw a clear hand curve through it so I don't think the data is the issue.
One example is attached. I would gratefully appreciate any tips, I'd consider it an early (and the BEST) Christmas present!
This is because the left most data point affects the fitting because the large y value potentially leads to large offset to the fitted curve. If you can assume the variation or uncertainty of each point is proportional to it's y value, you can probably add weight of 1/yi to each point. See below:
Exponential Curves Not Fitting Well
Posted - 12/17/2021 : 3:48:35 PM
