Search found 156 matches
- Thu Nov 15, 2012 5:14 pm
- Forum: MLwiN user forum
- Topic: Compare DIC
- Replies: 4
- Views: 8403
Re: Compare DIC
There is no theory based fixed difference e.g. 10 that should be compared when comparing the DIC of two models although 10 might have been a rule of thumb suggested by someone - in theory the model with the lowest DIC is better but of course there is stochastic noise when using MCMC so a very small ...
- Thu Nov 15, 2012 5:08 pm
- Forum: MLwiN user forum
- Topic: Changing values in Variance- Covariance matrix
- Replies: 3
- Views: 6678
Re: Changing values in Variance- Covariance matrix
Dear hdilk0507, I saw your question and have a quick answer. It really makes no sense to allow a level 2 variable to vary across level 2 units. Consider 1 level 2 unit then the predictor associated with the intercept will take value 1 for all individuals in the unit and the level 2 variable will als...
- Thu Oct 11, 2012 3:05 pm
- Forum: MLwiN user forum
- Topic: Residuals prediction and covariance-variance
- Replies: 1
- Views: 3740
Re: Residuals prediction and covariance-variance
Hi Econsic1976,
This is because the residuals are shrunken residuals - I think the answer might be quite technical and available in Harvey Goldstein's book or you could email him.
Regards,
Bill.
This is because the residuals are shrunken residuals - I think the answer might be quite technical and available in Harvey Goldstein's book or you could email him.
Regards,
Bill.
- Thu Oct 11, 2012 3:02 pm
- Forum: MLwiN user forum
- Topic: Zero variance question
- Replies: 2
- Views: 4798
Re: Zero variance question
Hi Mdommers,
I could take a look if you send me your worksheet (william.browne@bristol.ac.uk).
Regards,
Bill.
I could take a look if you send me your worksheet (william.browne@bristol.ac.uk).
Regards,
Bill.
- Tue Sep 11, 2012 2:08 pm
- Forum: MLwiN user forum
- Topic: predint.txt problems
- Replies: 1
- Views: 4264
Re: predint.txt problems
Hi Sian, My predint.txt macro is going to be tricky to replicate for bigger datasets - basically the following is done: 1) The residual chains have been stored stacked up in c200 - there are 130 of them as there are 65 schools (intercepts and slopes) 2) The school ids go from 1 to 65 which is import...
- Wed Jul 18, 2012 2:39 pm
- Forum: MLwiN user forum
- Topic: Variance disappearing in shift from 2- to 3-level model
- Replies: 4
- Views: 6954
Re: Variance disappearing in shift from 2- to 3-level model
Hi Matt, I am still a little puzzled. If as you say there are 13 categories for each GOR then a nested 3 level model should have 12 level 3 with 12*13 categories = 156 level 2 units. The only way that categories should be 13 would be if you had a cross-classified model. Am happy to take a look if yo...
- Thu Jun 28, 2012 2:23 pm
- Forum: MLwiN user forum
- Topic: Variance disappearing in shift from 2- to 3-level model
- Replies: 4
- Views: 6954
Re: Variance disappearing in shift from 2- to 3-level model
Hi Mattoftheday, your email puzzles me a little. When you say you have a structure of 12 > 13 > 84 do you in fact mean 12 GORS with 12*13 Categories within the 12 i.e. categories within GOR or do you mean you have a cross-classified structure with GOR crossed by Category ? Either way these sorts of ...
- Mon May 21, 2012 8:50 am
- Forum: MLwiN user forum
- Topic: one-tailed test for a predictor in MCMC
- Replies: 2
- Views: 7091
Re: one-tailed test for a predictor in MCMC
Hi Sian, I think you are a little confused here. The DIC diagnostic is an information criterion that can be used to compare models in a similar way to the AIC and BIC in a non-Bayesian/MCMC setting. What it is not is equivalent to 'a two-tailed test at 5% significance level'. The closest thing in th...
- Mon May 21, 2012 8:42 am
- Forum: MLwiN user forum
- Topic: question about a cross-classified model
- Replies: 2
- Views: 5711
Re: question about a cross-classified model
Hi Jelle, Yes this sounds appropriate for the analysis you intend to do. I would firstly look at each of the 2 ratings separately and fit a straightforward single response cross-classified model as in the chapter in my MCMC book. To fit a MV model you will need to follow the example in the MV Normal...
- Mon Aug 15, 2011 1:23 pm
- Forum: MLwiN user forum
- Topic: Cross-classified multinomial problems
- Replies: 2
- Views: 6953
Re: Cross-classified multinomial problems
This shouldn't be too bad in MCMC. Basically set up your model as in the MCMC manual chapter for multinomial then add on the extra levels as you would anyway. Ignore any error messages from IGLS. Switch to MCMC and tick the cross classified box as in the cross classified chapter in the MCMC manual. ...