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I estimated a MMNL which converged successfully. I am trying to simulate WTP for the ASC (ASC_low) which is normally distributed. My cost parameter is negatively log-normal distributed.
this is the code:
I received:
[1] NaN
[1] NA
I'm not sure what could be the reason for this.
These are the estimated values:
b_log_cost_mu = 1.186
b_log_cost_sig = -1.579
can you show us the model estimates too? It might be that you need to take the absolute values of the sigma parameters as the estimates might have been negative
Also, you're missing the minus sign in front of the exponential