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Student Support Forum: 'Best Fit Line / Regression Line' topicStudent Support Forum > General > Archives > "Best Fit Line / Regression Line"

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Afshin Esmaeili
08/06/08 09:43am

I have a set of non-linear data points and i want to plot the best fit line, but i have had no luck .... I did try google and the closest thing i got is this:

Nonlinear Curve Fitting: If your data does not follow a straight line or simple polynomial, you will need to use Mathematica’s NonlinearFit functions:

In[21]:= << Statistics‘NonlinearFit‘
Define the function and ask Mathematica to solve for a and b:
In[24]:= chrgft = NonlinearFit[chargedata,
a(1 - Exp[-x/b]), x, {a, b}]
Out[24]= 4.83133 (1 - ă-0.00957528 x)

The problem in my case is i don't know what function would best fit the data ... how do i do this ?

Here is sample data which i have: (I have attached a notebook with sample data if that helps )

{{1/6, 1/6}, {1/3, 1/2}, {1/6, 1/6}, {1/2, 1/3}, {1/6, 1/3}, {1/3, 2/
3}, {1/6, 1/3}, {2/3, 2/3}, {1/6, 0}, {1/3, 1/3}, {1/6, 0}, {1/2, 1/
6}, {1/6, 1/6}, {1/3, 1/2}, {1/6, 1/6}, {5/6, 5/6}, {1/6, 1/6}, {1/
3, 1/6}, {1/6, 1/6}, {1/2, 1/2}, {1/6, 1/3}, {1/3, 1/2}, {1/6, 1/
3}, {2/3, 1/2}, {1/6, 0}, {1/3, 0}, {1/6, 0}, {1/2, 1/2}, {1/6, 1/
6}, {1/3, 1/3}, {1/6, 1/6}, {1, 1/3}, {1/6, 1/6}, {1/3, 1/2}, {1/6,
1/6}, {1/2, 1/3}, {1/6, 0}, {1/3, 1/3}, {1/6, 0}, {2/3, 2/3}, {1/6,
1/3}, {1/3, 5/6}, {1/6, 1/3}, {1/2, 2/3}, {1/6, 1/6}, {1/3, 2/
3}, {1/6, 1/6}, {5/6, 1/3}, {1/6, 1/6}, {1/3, 1/6}, {1/6, 1/6}, {1/
2, 1/2}, {1/6, 0}, {1/3, 1/6}, {1/6, 0}, {2/3, 1/2}, {1/6, 1/3}, {1/
3, 1/2}, {1/6, 1/3}, {1/2, 1}, {1/6, 1/6}, {1/3, 1/2}}

Any help is greatly appreciated.

Thank you in advanced.




Attachment: SampleData.nb, URL: a.esmaeili@ucalgary.ca,

Subject (listing for 'Best Fit Line / Regression Line')
Author Date Posted
Best Fit Line / Regression Line Afshin Esmae... 08/06/08 09:43am
Re: Best Fit Line / Regression Line Forum Modera... 09/23/08 09:26am
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