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Thread: [SPSS - Logistic Regression] Resolve the linearity of logit assumption

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    [SPSS - Logistic Regression] Resolve the linearity of logit assumption




    I am running a logistic regression and my income variable violates the linearity of the logit assumption. It is not negatively effecting the goodness-of-fit statistics. I have transformed the variable into a log but that impacted the constant and made the odds ratio explode.

    When I square rooted the income variable, the constant was more stable. However, I am still violating the linearity of logit assumption.

    While I do not expect that income would behave in a linear fashion, I am unclear what to do --- should I leave the income variable alone and accept the violation of the assumption or is there a way to correct this issue?

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    Re: [SPSS - Logistic Regression] Resolve the linearity of logit assumption

    How aw you determining that the linearity of the logit has been broken?
    I don't have emotions and sometimes that makes me very sad.

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    Re: [SPSS - Logistic Regression] Resolve the linearity of logit assumption

    I ran the Box Tidwell test. I converted the Income variable by multiplying the income by its natural log. It was significant indicating the violation of the linearity of logit.

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    Re: [SPSS - Logistic Regression] Resolve the linearity of logit assumption


    Stop cowardice, ban guns!

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