Graphic to check for complete separation [closed]

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I need to check for complete separation. I am using SPSS and need to know what steps I have to take to get the grahpic on this site. Can someone help me?

Answer 1

SPSS does not provide that probability curve (SAS and Stata can do that). However, plotting the 1/0 outcome against the continuous predictor, and observe how the two horizontal data lines overlap may be enough to give you some hint.

If you have enough data, you can also first separate your data by different groups (for example, 10 equal groups split by your continuous predictors), and the compute each group's mean (aka probability of "yes" to outcome), and join the points. That line should approximate the curve in the illustration you provide.