I think Michael might be aware of this, but was hoping that the formula interface was as flexible as in R, which it is not. I believe there used to be support for more transformations in ~, but it was removed.
On Saturday, June 25, 2016 at 1:12:27 PM UTC+2, Douglas Bates wrote: > > On Friday, June 24, 2016 at 8:39:09 AM UTC-4, Michael Borregaard wrote: >> >> Sorry for asking a question that should be super-basic, but I have looked >> all over the internet for this for an hour now: How does one specify >> polynomial terms in glm models? >> >> In R, I would: >> >> y ~ x + I(x^2) >> >> Thanks! >> > > If you are using a DataFrame for the data source, just add a column > > df[:x2] = abs2(df[:x]) > > and change the formula to > > y ~ 1 + x + x2 > > BTW, it is good practice to include the " 1 + ". We are still considering > changing the formula interface to require the intercept to be explicitly > stated. > >
