On Sun, Apr 22, 2018 at 12:46 PM, Sven Schreiber <svetosch(a)gmx.net&gt; wrote: > Hi, > shouldn't this work: > > <hansl> > open CEL.gdt > series d = $unit > list a = dummify(d) # works > > list b = dummify($unit) # fails, datatype mismatch > </hansl> > > I guess the problem is that dummify needs a series name for the labels of > the dummies? But still... Not just the labels of the dummies, but also their names. Functions of this sort (that return a list of series derivative from some original series) require that the original series be a member of the current dataset, with a name and ID number. In the case of $unit (index of panel-data cross-sectional units), however, there's already an automated way of generating a set of dummy variables without adding $unit to the dataset under a user-specified name: it's genr unitdum