Re: st: iweights and ROC curves

[Steven Samuels <sjhsamuels@earthlink.net>]

I should have made clear: to get the ROC Curve, use ordinary - 
logistic-, not -svy: logistic-.  Mimic the -subpop- option with an - 
if- statement.

On Dec 11, 2008, at 7:30 PM, Steven Samuels wrote:

> Do not use iweights.-lroc- after -logistic- with frequency weights  
> works fine..
>
> Austin Nichols once pointed out that you can compute fweights that  
> give the same results as  pweights to any number of decimal places:
>
> For k decimal places, use
> new frequency weight = round(10^k * probability weight,1)
>
> So for 2 decimal places:
>
> 233.43 -> 23,343  a whole number.
>
>
> -Steve
>
>
> On Dec 11, 2008, at 1:30 PM, Patrick McCabe wrote:
> > Does any one know if the ROC curves produced by a logistic  
> > regression model using svy subpopulation and importance weights  
> > are 'legit'?  The resulting model is the same as the model  
> > produced with pweights but if you use pweights lroc does not work.
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