Estimating Standard Deviation by Using Curve Fitting Toolbox

5 vues (au cours des 30 derniers jours)
Joseph
Joseph le 27 Mar 2012
I am using Curve Fitting Toolbox to fit a 10 points data. Here's the result.
Linear model Poly1:
f(x) = p1*x + p2
Coefficients (with 95% confidence bounds):
p1 = 1.247e-013 (1.193e-013, 1.3e-013)
p2 = -1.544e-015 (-4.863e-015, 1.775e-015)
Goodness of fit:
SSE: 3.551e-029
R-square: 0.9972
Adjusted R-square: 0.9969
RMSE: 2.107e-015
I am neither using robust fitting nor with my own weighting factor. Therefore I suppose the SSE is not weighted and I can get the standard deviation by simply dividing the SSE by 10 (points) and take the square root of it. But is this correct?
May I also know in Curve Fitting Toolbox, the 95% confidence bound is equivalent to how many standard deviation? About 2 standard deviation by using the results obtained through Curve Fitting Toolbox?
If I did a robust linear fit, since the SSE is weighted, is there any way for me to get a good estimate of the standard deviation?
Here's the result for the robust fit:
Linear model Poly1:
f(x) = p1*x + p2
Coefficients (with 95% confidence bounds):
p1 = 1.239e-013 (1.182e-013, 1.297e-013)
p2 = -1.258e-015 (-4.831e-015, 2.315e-015)
Goodness of fit:
SSE: 4.116e-029
R-square: 0.9968
Adjusted R-square: 0.9964
RMSE: 2.268e-015
Thanks.

Réponses (0)

Catégories

En savoir plus sur Linear and Nonlinear Regression dans Help Center et File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by