You can try to hunt for it in the findbestsplit Fortran subroutine.  It
uses some thing that's equivalent (but easier to compute), not exactly
identical.  Breiman uses whatever computational shortcuts he could find
in his code.
 
Best,
Andy


________________________________

	From: Chrysanthi A. [mailto:chrysain@gmail.com] 
	Sent: Tuesday, September 29, 2009 4:55 PM
	To: Liaw, Andy
	Cc: r-help@r-project.org
	Subject: Re: [R] how to visualize gini coefficient in each node
in RF?
	
	

	Thanks for the reply! However, what is the code that is used in
order to calculate it.. Is it included in the "randomForest" R
function.. Because I am trying to find the code corresponding to the
estimation of the gini coefficient but I am a bit confused. Could you
please help me, by indicating me that? 

	thanks a lot,

	chrysanthi



	2009/9/29 Liaw, Andy <andy_liaw@merck.com>
	

		No.  The forest object is too large as is.  I didn't
think it's worth
		the extra memory to store them.  They were never kept
even in the
		Fortran/C code.
		
		Andy
		
		From: Chrysanthi A.
		> Sent: Monday, September 28, 2009 5:20 PM
		> To: r-help@r-project.org
		> Subject: [R] how to visualize gini coefficient in each
node in RF?
		
		>
		> Dear all,
		>
		> I am working with randomForest package and I am
interested in
		> examining the
		> "Gini importance" measures that are used as a general
		> indicator of feature
		> relevance. Is there a possibility of getting the Gini
measure
		> that is being
		> estimated in each tree by the output of the getTree()
function?
		>
		> Thanks a lot,
		>
		> Chrysanthi
		>
		
		>       [[alternative HTML version deleted]]
		>
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