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Thread: Non-linearity violation (predictor and log odds) in logistic regression with SAS

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    Non-linearity violation (predictor and log odds) in logistic regression with SAS




    Hi,
    I'm new to modelling and logistic regression, so I need a bit of help. I'm building a logistic regression model, and one of my continuous variables violates the linearity assumption (log odds). I can't categorise the continuous variable because I don't have enough events, so my only options are to add a quadratic or higher polynomial term, or fit splines. However, I have no experience with either, and I'm working with SAS and would have no idea what to enter into the code. As I mentioned before, I'm still learning, so reading online has been a bit of a challenge because the language is a bit advanced for me. Any help would be greatly appreciated. I've attached a picture of my data, from when I was first checking to see if it was linear or not.
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    Re: Non-linearity violation (predictor and log odds) in logistic regression with SAS

    Do you really only have 10 observations? How many events of interest do you have in the dependent variable (eg 50%)?

    Can you post the code you used to make the Loses or where you got the logic values from?

    Thanks!
    Stop cowardice, ban guns!

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    Re: Non-linearity violation (predictor and log odds) in logistic regression with SAS


    Is this a redundant post. If so, I am going to recommend they get consolidated!
    Stop cowardice, ban guns!

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