wbonat / mcglm

Fitting multivariate covariance generalized linear models
GNU General Public License v3.0
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Prediction and simulations #18

Open jingsliu07 opened 3 years ago

jingsliu07 commented 3 years ago

Dear authors, thanks for building the package and it has a great many applications in real-world modeling. This might be a stupid question but I couldn't find answers online - Is there a predict function to generate prediction on new data with mcglm models? Furthermore, if I want to run simulations on new data using mcglm models, are there any examples on how to do so? Thanks!

wbonat commented 3 years ago

Hi

Concerning predictions it depends on your model. If you have simple models for independent observations the predictions are easily obtained using the linear predictor. However, I do not have a generic method for the entire class, that's the reason I do not provide a prediction function.

In relation to simulations, the mcglm is based only on second moments, basically it means that we do not have a multivariate distribution available to simulate from it. Thus, I have used the NORTA (Normal to Anything) to simulate from mcglm models. It is a reasonable solution, but has limitations. I have used the NORTARA package in R to do it, but the specification of the NORTA algorithm is case specific, that's why the mcglm does not provide a generic function to simulate data from mcglm models.

Since, simulations are not implemented in the mcglm package I do not provide any documentation on it, but you can have a look at the NORTARA documentation's package.

Best wishes.