I came across the following puzzle while looking into bootstrapping
-lowess- curves: If the variable on the x-axis has ties, than I would
expect all observations with the same x value to have the same smoothed
y value. However if I generate smoothed values of y using -lowess- with
the generate option, observations with the same x value sometimes get
different smoothed y s, and this already occurs in the second digit, so
it seems too big for just rounding error. An example of this behavior
is given below.
*---------- begin example -----
sysuse auto, clear
lowess price rep78, gen(sm)
table rep78, c(min sm max sm)
*------------ end example -----
Maarten
-----------------------------------------
Maarten L. Buis
Department of Social Research Methodology
Vrije Universiteit Amsterdam
Boelelaan 1081
1081 HV Amsterdam
The Netherlands
visiting adress:
Buitenveldertselaan 3 (Metropolitan), room Z434
+31 20 5986715
http://home.fsw.vu.nl/m.buis/
-----------------------------------------
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