Hi, I have a question about ROCR package. I got the ROC curve plotted without any problem following the manual. However, I don't know to extract the values, e.g. y.values ( I think it is the area under the curve auc measure). The return is an object of class "performance" which have Slots and one of the slot is "y.values". I type the object and I can see them in screen. But I want to extract the value for further programming and computation. I did a summary of the object and it is a "S4" mode which I don't understand. Can someone help? Thanks a lot in advance. -- Waverley @ Palo Alto
If you post the code that you used, prehapsy using the sample data in
the same package, you may get more useful replies:
"commented, minimal, self-contained, reproducible code."
Gee, ... where have I seen that before?
Also could see the thread;
https://stat.ethz.ch/pipermail/r-help/2009-February/186754.html
....posted last week. The preferred method is to use the proper
extractor functions, but since you provided no code we cannot look at
your objects. Looking at the documentation for perfomance-class
objects I do not see mention of y.values.
--
David Winsemius
On Feb 7, 2009, at 3:17 PM, Waverley wrote:
> Hi,
>
> I have a question about ROCR package. I got the ROC curve plotted
> without any problem following the manual. However, I don't know to
> extract the values, e.g. y.values ( I think it is the area under the
> curve auc measure). The return is an object of class
"performance"
> which have Slots and one of the slot is "y.values". I type the
object
> and I can see them in screen. But I want to extract the value for
> further programming and computation. I did a summary of the object
> and it is a "S4" mode which I don't understand.
>
> Can someone help?
>
> Thanks a lot in advance.
>
> --
> Waverley @ Palo Alto
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
Dear Waverley, Try this: unlist(slot(perf,"y.values")) See ?slot for more details. HTH, Jorge On Sat, Feb 7, 2009 at 3:17 PM, Waverley <waverley.paloalto@gmail.com>wrote:> Hi, > > I have a question about ROCR package. I got the ROC curve plotted > without any problem following the manual. However, I don't know to > extract the values, e.g. y.values ( I think it is the area under the > curve auc measure). The return is an object of class "performance" > which have Slots and one of the slot is "y.values". I type the object > and I can see them in screen. But I want to extract the value for > further programming and computation. I did a summary of the object > and it is a "S4" mode which I don't understand. > > Can someone help? > > Thanks a lot in advance. > > -- > Waverley @ Palo Alto > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. >[[alternative HTML version deleted]]