linearity assumption

[shahd]

If I want to make sure about the linearity assumption

Does the relationship between categorical variable and y in any model should be nonlinear as it always has the same trend. how can the other plots help me to determine the relationship and if I need any specific type of transformation 

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[PaigeMiller]

If you ask me, the idea of fitting a straight line (or any line) to your data is completely off target and wrong. You have categorical X, you want to fit an appropriate model for categorical X, which could be PROC GLM where X is in the CLASS statement.

[shahd]

for my understanding, the GLM for categorical y variable. Here x is the categorical I am looking to check the linearity between x and y here. Could you please advise with this

[PaigeMiller]

From your plots, the categorical variable is the X variable.

There is no such thing as linearity with a categorical X variable.

[shahd]

I need to decide if this relationship between x and y is linear or non-linear so if its non-linear I need to transform the x

[PaigeMiller · Accepted solution]

Honestly, @shahd, I think you are headed down the wrong path here. I think you are asking meaningless questions. There is no such thing as linearity in the case where you have a categorical X variable.