Hi, Robin.

Thanks for your  wonderfulreply ! it makes me understand this algrithms
further.

But, i still have some questions.

On Thu, Jul 29, 2010 at 6:37 AM, Robin Anil <[email protected]> wrote:

> This is not regular FPGrowth. This has many other super improvements ;)
>
> 1) Its a faster method for mining of Top K patterns for each unique item:
> How does it do it? First it makes the conditional tree for each feature in
>

I think the growth() function works in this way.


> Bottom up manner(like the paper). Then it mines the conditional tree in top
>

and, the  growthTopDown() function works as this manner( from top nodes to
mining the frequent patterns, as you said, it will make the mining process
fast).

But i still can't understand why this function should  use the
growthBottomUp(). it seems that this growthBottomUp() function works like
the growth() function from bottom node to top in the headerTable.

growth() -> growthTopDown() -> growthBottomUp()

Maybe, you just can help to explain how the growthBottomUp() works here.

Thanks!

down manner. This ensures it mines the top frequent sub patterns into a Heap
> or in this case a PriorityQueue which allows me to remove the least
> frequent
> item easily. So everytime my queue is full and the support of the item in
> the tree falls below that of the first entry in the Queue, I stop mining.
> This makes it really really fast.  Also I try to mine only the closed
> patterns. See below:
> If,
> A,B,C => 4
> and
> A, B => 4.
> I select only the first as second is already part of first.
>
>
> 2) The intermediate data which gets thrown in the map/reduces looks like an
> FPTree called the Pattern tree. So I am able to compress more data making
> the whole process faster
>
> 3). While making conditional trees, I try to zip them up and prune nodes
> which fall below the min support. This is called FP-Bonsai algorithm. This
> is blazing on tree which have a huge depth.(i.e the input data is having
> longer transactions)
>
>
> Hope this clears up your questions. Please take a look at the original
> https://issues.apache.org/jira/browse/MAHOUT-157 issue. You will see how I
> progressed from standard FPGrowth to this. Search mailing lists for older
> discussions
>
> Robin
>
> On Tue, Jul 27, 2010 at 11:55 PM, Andrew Wang <[email protected]
> >wrote:
>
> > Ye, thanks for your reply, Ted.
> >
> > As you know, after construct the FP-tree, we will use the growth fuction
> to
> > produce the frequent patterns.
> >
> > As the paper (Mining Frequent Patterns without Candidate Generation)
> > described, we should get the patterns from the bottom of the
> > HeaderTableAttributes (which always are leaf nodes in the pt-tree).
> >
> > So, maybe we just need to growthBottomUp() function. But, i also see
> > growthTopDown() function in the FPGrowth.java.
> >
> > I just confused with this two functions, what are the differeces between
> > them?
> >
> > Wish i describe my question clearly now.
> >
> > thanks
> >
> > On Wed, Jul 28, 2010 at 2:29 PM, Ted Dunning <[email protected]>
> > wrote:
> >
> > > What is it that you don't understand about it?
> > >
> > > If you can give specific questions, you are much more likely to get a
> > good
> > > answer.  The paper that you already have should give you most of the
> > > general
> > > hints that you need.  From there, you should provide specific
> questions.
> > >
> > > On Tue, Jul 27, 2010 at 10:13 PM, Andrew Wang <
> > [email protected]
> > > >wrote:
> > >
> > > >        Now, only the growth(FPTree tree, MutableLong
> minSupportMutable,
> > > int
> > > > k, FPTreeDepthCache treeCache, int level, int currentAttribute,
> > > > StatusUpdater updater) function in the FPGrowth.jave cannot be
> > understood
> > > > by
> > > > myself.
> > > >
> > > >        Would you please tell how it works? or give me some papers to
> > help
> > > > me to understand it? thanks!
> > > >
> > >
> >
> >
> >
> > --
> > http://anqiang1900.blog.163.com/
> >
>



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http://anqiang1900.blog.163.com/

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