*
* Example 16.9 page 458
*
open data tablef5-2[1].txt
data(format=prn,org=columns) 1 123 id year cost q pl sl pk sk pf sf
*
* The original data set isn't ordered on q, so we reorder it, as the data cutoff
* is based upon q. It appears as if the data used this time are observations
* 6-111, which eliminates the (rather thin) collection of observations with
* output greater than 25000.
*
order(all) q
set avgcost = 1000.0*cost/q
*
npreg(bandwidth=2000,type=logit) avgcost q 6 111 kxfit kyfit
scatter(style=dots,overlay=line,ovsame,footer="Figure 16.6 Non-Parametric Regression for AVGCOST",$
  hlabel="Output",vlabel="E[AvgCost|O]") 2
# q avgcost 6 111
# kxfit kyfit
*
* The scatter plot looks somewhat different in the 15000+ range because the RATS
* NPREG instruction does (by default) an equally spaced grid, while the output in
* figure 16.7 uses an "x" grid which matches the observed x values, which are
* rather sparse out in that area.
*
npreg(bandwidth=200,type=logit) avgcost q 6 111 kxfit kyfit
scatter(style=dots,overlay=line,ovsame,footer="Figure 16.7 Non-Parametric Regression for AVGCOST",$
  hlabel="Output",vlabel="E[AvgCost|O]") 2
# q avgcost 6 111
# kxfit kyfit