Believe what you are looking for is the Regression option for the meanspec
https://s-broda.github.io/ARCHModels.jl/dev/univariatetypehierarchy/#meanspec
Believe what you are looking for is the Regression option for the meanspec
https://s-broda.github.io/ARCHModels.jl/dev/univariatetypehierarchy/#meanspec