[R-sig-ME] mgcv: 3D tensor product smoothers and ti()

[Ben Bolker]

Mark Payne <markpayneatwork at ...> writes:

> 
> Hi,
> (PS This was originally posted to r-help, but didn't get a reply, so
> am trying again here)
> 
> I am trying to fit a smoothing model where there are three dimensions
> over which I can smooth (x,y,z). I expect interactions between some,
> or all, of these terms, and so I have set up my model as
> 
> mdl <- gam(PA ~ s(x) + s(y) + s(z) + te(x,y) + te(x,z) + te(y,z) +
> te(x,y,z),...)
> 
> I have recently read about the ti(), "tensor product interaction
> smoother", which takes care of these interaction terms elegantly and
> does the nesting properly.

  [snip] to make gmane happy ...


  Appreciate that you would like help with this, but this is really
very distantly (at best) related to mixed models ... is there perhaps
an example in Simon Wood's book?

  Ben Bolker