🚀 go-pugleaf

In article <1992Sep9.150541.15735@cbfsb.cb.att.com>, rizzo@cbnewsf.cb.att.com (anthony.r.rizzo)
asks about the propriety of constraining a fitted quartic to pass through
a given point:
> 
This sort of thing is often done in linear regression, usually to make the
line pass through the origin. There is no objection to doing this, but it
makes the fit slightly worse elsewhere.

I have greater reservations about using a quartic. The higher degree
the polynomial, the more unstable it is. I hope you fitted it by using
orthogonal polynomials which helps with numerical stability.

I don't say it is wrong to use high degree polynomials, just be careful;
draw and examine residual plots etc (you should do this anyway).