I am estimating alpha and lambda for each participant at each time point from the following code. Therefore, I need to add two random effects. How do I do this in R?
Both betas are fixed.
` b0 = 1 b1 = 5
logistic_growth_model <- nls(stage ~ b0 + (b1 - b0) / (1 + exp(-alpha * (age - lambda))), data = df, start = list(alpha = 0.9, lambda = 13.5))
summary(logistic_growth_model) `
I think I can use "gnls" or "nlme" to do what I need to do but I'm having trouble with the syntax to add random effects and keep both betas fixed.