On Sun, 2 Jun 2019, Fred Engst wrote: > I noticed a line of code that I didn’t know was possible from your > response earlier: > > "ols lwage 0 log(wage) —simple” > > Here you’ve invoked a function on the command line, i.e. log(wage), > not a existing series’ name. Other transformation is also possible, > such as ols y 0 y(-1 to 4) that I’ve noticed. This raises a question > about the nature of the indepvars in the ols documentation. What > other command line transformation that is possible without creating > a new variable first?
The argument passed to ols and related commands is a list (of series) and a list can only contain named series (members of the dataset, with ID numbers). So you can employ any function that returns a list, or that creates a named series. This includes log, lags, diff, ldiff, sdiff, square, dummify, cdummify, dropcoll You cannot, for example, do ols y 0 x^3 because "x^3" just gives an anonymous result, that must be assigned a name and ID number before it can feature in a list. This isn't documented as such; it probably should be. But for each of the relevant functions it's documented that they either return a list or create an automatically named series. Allin
