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Define axis intercept for regression

LawOfWolf466
Level I

Hello,

Is it possible to specify the intercept for a linear regression under Fit Model?

This means that JMP does not freely select the value for "a" in the linear function y= a+b*x1+c*x2+.... but sets it to 1, for example.

Thanks.

 

1 ACCEPTED SOLUTION

Accepted Solutions


Re: Define axis intercept for regression

Here's a thought: Rearrange the regression equation.

y-a = b*x1+c*x2+...

 

This suggests that you can create a new formula data column that subtracts off your desired intercept a from the response variable y. Then run fit model on the new column using the "No Intercept" option (effectively setting the intercept to zero). You can re-add the desired intercept to the resulting prediction expression.

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2 REPLIES 2


Re: Define axis intercept for regression

Here's a thought: Rearrange the regression equation.

y-a = b*x1+c*x2+...

 

This suggests that you can create a new formula data column that subtracts off your desired intercept a from the response variable y. Then run fit model on the new column using the "No Intercept" option (effectively setting the intercept to zero). You can re-add the desired intercept to the resulting prediction expression.


Re: Define axis intercept for regression

You can also specify such a model using the Nonlinear platform, but it is not as convenient as using Fit Least Squares with @Jordan_Hiller's trick.