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LC model with covariate

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suzanakarim
Posts: 2
Joined: 15 May 2020, 08:11

LC model with covariate

Post by suzanakarim »

Hi,
I am new to this forum.
Currently, I am working on the LC model with covariates (EM algorithm), apollo_exercise 28. I am confused about the function apollo_probabilities_class.
Specifically, why are we exponentiating the following expression, if our goal is to calculate eq 11.5 in manual?

P[["model"]]=exp(Reduce('+', mapply('*',h_grouped,log_pi_values,SIMPLIFY = FALSE)))

I might miss something obvious. ANy explanation to this would be really appreciated

Thanks
Suzana
stephanehess
Site Admin
Posts: 974
Joined: 24 Apr 2020, 16:29

Re: LC model with covariate

Post by stephanehess »

Hi Suzana

this is the likelihood equivalent of Equation 11.5. I have clarified this in the manual for v.0.1.1. Please also consult Eqn 14 in https://www.caee.utexas.edu/prof/bhat/A ... egment.pdf

Best wishes

Stephane
--------------------------------
Stephane Hess
www.stephanehess.me.uk
suzanakarim
Posts: 2
Joined: 15 May 2020, 08:11

Re: LC model with covariate

Post by suzanakarim »

Dr. Stephane,
Thank you very much. I understood it.

Suzana
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