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Hi George,

Many thanks for your response and your suggestions – much appreciated.

I have followed your suggested strategy on building up the model gradually and using the results from the previous model as the starting values. However, unfortunately, I am still getting error messages on the ...

Dear runmlwin users,

I am trying to explain variability in length of hospital stay using a multilevel Poisson model (at the moment, I am interested in two levels – patients clustered within hospitals – but I would like to extend this to incorporate other levels and non-hierarchical structures). I ...

Dear George,

Thank you very much for your very helpful response.

Kind regards,

Jacqueline

Dear runmlwin users,

I have two questions with which I was hoping you could please help.

First, I am analysing data that could be described as count data and that exhibit over-dispersion. Thanks to Chris, I understand that the negative binomial distribution is not implemented currently in MLwiN ...

Hi Chris,

Thank you very much for your response.

Kind regards,

Jacqueline

Dear runmlwin users,

I am trying to analyse count data using a negative binomial distribution with a log link function. I have chosen a negative binomial distribution because the data exhibit overdispersion. As recommended for discrete response models, I am estimating the model with MCMC. When I ...

Hi George,

Thank you for your response. I will try changing the starting values as you suggest.

Kind regards,

Jacqueline

Hi George,

You were absolutely correct - the models have been running fine since I updated the version of runmlwin. Thank you for your advice!

Just one other question - for some of the MCMC models (usually the more complex ones), I receive a message in MLWiN that 'Matrix must be positive definite ...

Hi George,

Thank you very much for your response. I will work through your suggestions and let you know how I get on.

Many thanks,

Jacqueline

Dear runmlwin users,

I am trying to run a multiple membership model using runmlwin. My data are hospital discharges and are structured as patients, who can be treated by multiple consultants, clustered within hospitals. When I run a null model (even just with patients as multiple members of ...