question 1 -

While estimating 3 parameters the Identification strength with moments Information matrix (log−scale), show no bars and matlab informs that all variables are collinear with each other.

However when I estimate any two separately the bars appear and all variables are identified.

I was wondering how to correct or explain this behaviour ?

question 2 - Also the posterior means change for parameters when I add one more parameter to the subset of parameters to be estimated ? Is there any rule of thumb if we need to estimate a certain number of parameters ? The acceptance ratio is 30%. Can increasing the number of metropolis hastings replications solve this problem ??

Regards,