Smooth Curves in a Contour Plot?

[Alexis Corda]

Hello! I've played around with the contour plot command and am wondering if there are ways to smooth the curves in the graph. I've tried to include the image below.

I've used 4 levels and I have tried different interpolation methods but they all look the same.

Any advice? Thanks!

[Alexis Corda]

If someone knows that this isn't possible in STATA, then that info would be good to know too!

[Nick Cox]

The goal of contouring is in essence to interpolate smooth curves consistent with the data. If you want something even smoother, you need to suggest what you will give up, as then you're modelling the data given the coordinates and accepting some degree of misfit. There are many regression-like methods (e.g..polynomials in the coordinates) but they have often proved disappointing.