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I am trying to get a bootstrap pvalue from my latent class analysis using the following commands: LRTSTARTS = 40 8 40 8; OPTSEED = 861413; LRTBOOTSTRAP = 100; But I am getting the following warning: WARNING: THE BEST LOGLIKELIHOOD VALUE FOR THE 3 CLASS MODEL FOR THE GENERATED DATA WAS NOT REPLICATED IN 81 OUT OF 100 BOOTSTRAP DRAWS. THE PVALUE MAY NOT BE TRUSTWORTHY DUE TO LOCAL MAXIMA. INCREASE THE NUMBER OF RANDOM STARTS USING THE LRTSTARTS OPTION. Where 3 classes is the K1 class model. In running the analysis without bootstrap and STARTS 40 8 the 3 (k1) class model output looks ok (the best likelihood is replicated 8 times)  so what is going wrong in this bootstrap? Also in all of the documentation I have seen, it is advised to use 0 0 in LRTSTARTS for the k1 model  why is this the case? and what is going wrong in my case? Thanks in advance 


Web Note 14 might be helpful  you find it on our web site: Asparouhov, T. and Muthén, B. (2012). Using Mplus TECH11 and TECH14 to test the number of latent classes. Mplus Web Notes: No. 14. May 22, 2012. 


I have consulted webnote 14 and followed the procedure for determining number of lrstarts for the k class model and for determining the OPTSEED. I am confused because the warning I get refers to the k1 generated data and according to webnote 14 the generated data are generated according to the k1 model, so what could be going wrong for k1 likelihoods in the generated data to not be replicated? 


There is a typo in that error message. It should have been WARNING: THE BEST LOGLIKELIHOOD VALUE FOR THE 4 CLASS MODEL FOR THE GENERATED DATA WAS NOT REPLICATED IN 81 OUT OF 100 BOOTSTRAP DRAWS. THE PVALUE MAY NOT BE TRUSTWORTHY DUE TO LOCAL MAXIMA. INCREASE THE NUMBER OF RANDOM STARTS USING THE LRTSTARTS OPTION. So try LRTSTARTS = 0 0 150 40; 


Thanks Tihomir, that worked fine. 

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