Dear Magnus, this is a toobox I downloaded from internet few months ago (I forgot where from, actually). Anyway, it's working. I hope this may help you.

Thanks! It seems like a project or platform called Dynare is the origin of at least some of the files:

https://github.com/DynareTeam/dynare/tree/master/matlab/gsa

May I ask in what application do you use group sampling? My application is Modelica simulation models of aircraft vehicle systems (e.g. hydraulics, cooling, or fuel systems) with lots of uncertain parameters/inputs and lots of outputs, an in addition the models execute fairly slow.

I use it mostly for model updating of structural and dynamic parameters using feedback from experimental modal analysis testing. It may happen that you have very big FE models with different parameters and you may want to tune these parameters to fit the experimental response.