get_vcov: Get the variance-covariance matrix of a gamlss object in any...
In MiguelRodo/gamlssutils:

Description Usage Arguments Details Value Examples

View source: R/vcov_env.R

The vcov.gamlss method relies on the object passed to the data parameter of the call to gamlss::gamlss to be found in the global environment. However, this may well not be the case, especially if the object were fit inside a function. The object may also exist but have changed its value.

It would be ideal to simply pass the dataframe to vcov.gamlss directly, but that would need to adjust the gamlss package (as I don't know how to create the same package but with a different name and this slight adjustment), which I would rather avoid.

So, this function assigns the dataframe to the global environment with the name that was passed to mod.

1	get_vcov(mod, data, data_name)

`mod`	gamlss object. Object of class gamlss.
`data`	dataframe. Dataframe originally passed to `data` parameter in `gamlss` function used to fit `mod`.
`data_name`	character. Name of object passed to `data` parameter in `gamlss` function used to fit `mod`.

It's unclear what would happen under parallel processing or if the user were altering this object in the global environment as well.

Variance-covariance matrix as output by vcov.gamlss.

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data_test <- data.frame(x = runif(10))
data_test[['y']] <- 3 * data_test[['x']] + rnorm(10, sd = 1)
mod_gam <- gamlss::gamlss(y ~ x, data = data_test)