Search found 156 matches
- Thu Nov 28, 2013 9:34 am
- Forum: MLwiN user forum
- Topic: 3 level model: problems with cov matrix at level 2
- Replies: 1
- Views: 3157
Re: 3 level model: problems with cov matrix at level 2
Good Morning Claudia, It is as you have surmised possible for the IGLS method that really works on the full covariance matrix of the observations to construct parameter estimates that when evaluated as for example between school variances, correlations etc. give implausible values for this interpret...
- Mon Nov 25, 2013 1:20 pm
- Forum: MLwiN user forum
- Topic: Multilevel modelling for categorical repeated measures data
- Replies: 5
- Views: 6957
Re: Multilevel modelling for categorical repeated measures d
Hi bgawarammana, To add to the last reply. Having spoken to colleagues this comment was made in quite an old version of the manual and has persisted. The main issue with repeated measures binary data is the assumption of normality for the individual random effects is often not satisfied by the data....
- Mon Nov 25, 2013 11:41 am
- Forum: MLwiN user forum
- Topic: Multilevel modelling for categorical repeated measures data
- Replies: 5
- Views: 6957
Re: Multilevel modelling for categorical repeated measures d
Hi bgawarammana, It is possible to fit multilevel binary/categorical response models to data that have a structure of repeated measures within individuals. However just like all repeated measures models the assumption is that the correlation between individual data points is equal and doesn't depend...
- Wed Aug 14, 2013 1:12 pm
- Forum: MLwiN user forum
- Topic: BIC with MLwin?
- Replies: 1
- Views: 12400
Re: BIC with MLwin?
Hi Sinavera, MLwiN only calculates the deviance (-2LL) though generally BIC is a simple formula involving this quantity and the number of parameters in the model and number of observations in the dataset. Things are not quite as simple in multilevel models as there is some disagreement onto what one...
- Wed Jul 03, 2013 9:52 pm
- Forum: MLwiN user forum
- Topic: HELP setting up multiple membership model
- Replies: 4
- Views: 14876
Re: HELP setting up multiple membership model
Hi Diego, I think you are best transforming your data into long format and fitting a cross-classified model with exam score nested within pupil and school. That way you can easily include time varying covariates as you have 1 response per year. The alternative/extension where you make the school cla...
- Tue Jul 02, 2013 9:35 am
- Forum: MLwiN user forum
- Topic: HELP setting up multiple membership model
- Replies: 4
- Views: 14876
Re: HELP setting up multiple membership model
Dear DrDTorres, My main concern here is whether your response is 1 per year ? If so then you simply have a simple 3 level model. If you want to do something more complicated then as I see it you have several choices. You could fit a variant of a cross-classified model which is in fact a 3 level nest...
- Wed Jun 12, 2013 9:39 am
- Forum: MLwiN user forum
- Topic: multivariate Wald test
- Replies: 1
- Views: 8242
Re: multivariate Wald test
Dear mwkoeter, The intervals and tests window under Estimation will do this. You simply choose the fixed button at the bottom of the screen and increase # of functions to 3. Then for each column place a 1 next to 1 of the 3 dummies ( a different one for each column) and click calc to get the chi-squ...
- Mon Mar 18, 2013 11:58 am
- Forum: MLwiN user forum
- Topic: spatial modeling
- Replies: 1
- Views: 4151
Re: spatial modeling
Dear user, I'll be honest with you and say that I am not sure I have ever tried a binary response model with spatial random effects. The majority of the time in disease mapping which is the field for which I coded the CAR modelling section the responses are treated as counts and fitted as Poisson. I...
- Thu Jan 31, 2013 12:58 pm
- Forum: MLwiN user forum
- Topic: Multilevel Multiple Imputation
- Replies: 2
- Views: 5279
Re: Multilevel Multiple Imputation
Dear medha001, Just last week we came across a similar issue. The problem is if you have individuals who are missing on all responses then this causes issues with MLwiN when you switch to MCMC. We have made a change that will fix these issues, which will appear in the next version 2.27 but strictly ...
- Fri Nov 16, 2012 8:24 am
- Forum: MLwiN user forum
- Topic: Changing values in Variance- Covariance matrix
- Replies: 3
- Views: 6710
Re: Changing values in Variance- Covariance matrix
Hi, In the situation in which you have level 1 variables that you make random at level 2 and for some reason IGLS gives a non-positive definite answer then the advice is to change the values prior to running MCMC so that they make sense. The values you choose have 2 roles - (i) starting values for t...