regression method (in matlab)

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Hi
I have two curves , one is measured one is calculated from cylinder. They are all angle dependent.
Angle->Pressure
Would you offer any matlab function that I calculate the regression with these two datas.
I am searching the qaulity of simulation regarding to measurement? The matrixes are like that
The Matrix A is (measured)
Angle Pressure
----- ------
1 3,35000000000000
2 3,33000000000000
3 3,31000000000000
4 3,35000000000000
5 3,31000000000000
....
the Matrix B (simulated)
Angle Pressure
----- --------
1 3,12302310000000
2 3,10574540000000
3 3,08854990000000
4 3,07221170000000
5 3,05751980000000
Best Regards.
  2 个评论
Star Strider
Star Strider 2012-7-7
编辑:Star Strider 2012-7-7
What regression model are you considering?
Orkun OZENER
Orkun OZENER 2012-7-7
Dear Star Rider.,
I tried lineer regression model for obtaining how two data is connected to each other... The mean average values of two data sets are 3,256 and 3,4... But lineer regression gives 0,75 regression...So I I am really confused.. ı am open two all methods.

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采纳的回答

Image Analyst
Image Analyst 2012-7-7
Have you looked at polyfit()?
  2 个评论
Orkun OZENER
Orkun OZENER 2012-7-7
Actually I am lookig a thing like the how the two series is connected to each other...I dont want to fit a polynom...
Image Analyst
Image Analyst 2012-7-7
编辑:Image Analyst 2012-7-8
You mean like a correlation coefficient, or RMS error, or PSNR? Usually you don't regress simulated vs. measured (i.e. predicted vs. observed). You could use scatter() to see them plotted against each other but usually you don't do a regression to fit a line through the points. Often/Usually you'll use PSNR to see how well your model/simulation did in predicting the observed values, at least in compressing and reconstructing data. Other fields may have other methods that are preferred, such as RMS error or average absolute difference or MSI or SSIM ( http://en.wikipedia.org/wiki/Structural_similarity)

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更多回答(2 个)

Star Strider
Star Strider 2012-7-7
You list one set of data as being ‘measured’ and the other as ‘simulated’. Are you comparing the fit of the simulation to the measured data? If so, then the best measure to describe their relationship might be the mean-square error:
MSE = mean((measured-simulated).^2);
The RMS error Image Analyst refers to is:
RMS = sqrt(MSE);

Kazim Hanbay
Kazim Hanbay 2012-8-9
soru hakkında şunu söyleyebilirim;Her iki dağılımın olasılık yoğunluk fonksiyonlarını hesaplayıp daha sonra lineer reg. deneyebilirsiniz sanırım.Ayrıca size bir şey sormak istiyorum.Bir görüntünün korelasyon matrisini nasıl hesaplayabilirim?Daha sonra bu matrisin öz değer ve öz vektör analizini yapmam gerekiyor.
  2 个评论
Walter Roberson
Walter Roberson 2012-8-10
Mechanical translation of above (Google):
I can say about the question, the probability density functions of both distributions and then calculate the linear reg. I guess you can try. Also I want to ask you something. How do I calculate the correlation matrix of an image? Then I need to do an analysis of this matrix eigenvalues and eigenvectors.
Orkun OZENER
Orkun OZENER 2012-9-2
Dear Hanbay,Thanks for your answer. On the other hand I really dont know how you can do the thing that you asked.? Sorry . Best Regards.

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