Kieran's reference was entirely pertinent. -mkspline, cubic- calculates restricted cubic splines, as from Stata 10.
Nick
[email protected]
Jacob Wegelin
Thanks. Actually, -mkspline- computes *linear* splines. For instance,
the following code:
. mkspline Age1 44 Age2 = Age
. regress Y Age1 Age2
fits a continuous, piecewise linear model of E(Y|Age) for which the
slope is permitted to change abruptly at Age=44.
Thus I am looking for a reference that specifically explains what
algorithm and formulas are implemented in -mkspline-, and perhaps also
discusses uses of linear splines and gives examples where they are
used to good effect.
On Tue, May 5, 2009 at 7:05 PM, Kieran McCaul <[email protected]>
> Frank Harrell's book "Regression Modelling Strategies" has a chapter on
> restricted cubic splines.
Jacob Wegelin
> Can anyone point me to a reference for -mkspline- ?
>
> I mean, ideally, a published article or book that describes in
> software-independent terms (so that statisticians who do not know
> Stata will understand) exactly the algorithm and/or formula that the
> Stata programmers implemented when they wrote -mkspline-.
>
> I apologize if the answer is in [R] Stata Reference Manual. I do not
> own that book.
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