Hello, Statalist Users,

This is an exploratory question: Is it possible to carry out a piecewise linear model in which the linear predictor (time in this case) only has four time points? The outcome at each time point is a score. I want three slope segments so that I can compare the equality of the middle slope between two or more groups.

Seems like I need a continuous predictor with a greater range that I can then divide into segments. Though time is continuous, those four time points are basically discrete in my thinking.

Alternative approaches are welcome.

D

This is an exploratory question: Is it possible to carry out a piecewise linear model in which the linear predictor (time in this case) only has four time points? The outcome at each time point is a score. I want three slope segments so that I can compare the equality of the middle slope between two or more groups.

Seems like I need a continuous predictor with a greater range that I can then divide into segments. Though time is continuous, those four time points are basically discrete in my thinking.

Alternative approaches are welcome.

D

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