T O P I C R E V I E W |
HAMZA_2022 |
Posted - 09/08/2022 : 09:29:52 AM Origin Pro.2016(64bit) b9.3.226, OS=windows10
i m working on the gaussian fitting of my data; my data vector contain 950 points and when i performed the fitting with a gaussian function given by origin, the Reduced Chi_sqr value performed by the origin seems to be too small and equal to 0.00392, so the degree of freedom DOF in my case is 946 (=number of data points-number of parameters to be estimated by the fit). my question is how can i evaluate the goodness of my fit, is the value of reduced Chi_sqr is good? i calculate the Chi_sqr by the formula: Chi_Sqr=Reduced Chi_Sqr*DOF= 0.00392*946 = 3.7, is this value good? is the fit is good? the fit was performed usinf weighted Instrumental, is this correct? ------- before i did the same fit with no weight, the reduced Chi-SQR was too long >50 what is the problem? thanks how about the Adj.R-Square= 0.98944?
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2 L A T E S T R E P L I E S (Newest First) |
HAMZA_2022 |
Posted - 09/11/2022 : 06:07:22 AM thanks for your response, now i repeat the fit with different function in the weight, so i found the Reduced_Chi-Sqr=1.0045 and the Adj.R-Square=0.9966. is this fit good?
quote: Originally posted by YimingChen
A reduced chi-square value close to 1 indicates a good fit. In your case, it indicates the error values are too large if used as weighted instrumental. Other than reduced chi-square, you can check R-Square or Adj. R-Square to tell the goodness of fit. A value close to 1 indicates a good fit. Please also refer to this page: https://www.originlab.com/doc/Quick-Help/Bad-ReducedChiSqr
James
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YimingChen |
Posted - 09/08/2022 : 2:11:26 PM A reduced chi-square value close to 1 indicates a good fit. In your case, it indicates the error values are too large if used as weighted instrumental. Other than reduced chi-square, you can check R-Square or Adj. R-Square to tell the goodness of fit. A value close to 1 indicates a good fit. Please also refer to this page: https://www.originlab.com/doc/Quick-Help/Bad-ReducedChiSqr
James |
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