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Polynomial regression terms for logistic regression in SPSS Statistics

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Question

I have a binary dependent variable (Y) and a continuous predictor (X) and wish to perform a logistic regression. I would like to add a quadratic term for X, i.e. X squared, to the model and test its contribution to the model. I can see how interaction terms can be added to the model in the Binary Logistic Regression dialogs, i.e., highlighting all terms involved in the interaction in the variable list on the left of the main dialog, then clicking the ">a*b>" button to enter the interaction term in the Covariates box. However, I do not see a way to entered a polynomial term for a predictor into the covariates box. How can a polynomial model be run in SPSS Statistics?

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Modified date:
17 June 2026

UID

swg21640516

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