Jerry Friedman advocated a few mods to RF in his "ISLE" algorithm:
 
- draw smaller samples
- grow smaller trees
- "post process" the forest using something like PathSeeker (or LASSO)
 
Andy

________________________________

From: Wensui Liu [mailto:liuwensui@gmail.com]
Sent: Fri 3/20/2009 4:46 PM
To: Liaw, Andy
Cc: Anirudh Kondaveeti; r-help@r-project.org
Subject: Re: [R] Pruning trees in a Random Forest



I don't think it necessary to prune trees in RF, per brieman's paper.

On 3/20/09, Liaw, Andy <andy_liaw@merck.com> wrote:
> The way the trees are structured in randomForest, there's no way to stop
> tree growth by depth (what you called level).
>
> (If anyone has ideas, I'm all ears.)
>
> Andy
>
> From: Anirudh Kondaveeti
>>
>> Hi all!
>>
>> The randomForest in R enables us to prune the trees using the nodesize
>> feature where we can stop splitting a node if it contains
>> less than the
>> specified no.of of records/entities at that node.
>>
>> However is there a way to stop the tree growing after a
>> specified number of
>> levels. To be more clear on what I mean by a level. Level 0
>> is the parent
>> node, Level 1 has 2 daughter nodes, Level 2 has 4 daughter
>> nodes, Level 3
>> has 8 daughter nodes etc.
>>
>> Thanks in advance!
>>
>> Anirudh Kondaveeti
>> ----------------------------
>>
>>      [[alternative HTML version deleted]]
>>
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>>
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> ______________________________________________
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>


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