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From Angus Macnab <angus.mac...@gmail.com>
Subject Re: Classify Handwritten Digits
Date Fri, 24 Jan 2014 16:46:49 GMT
You can do supervised learning by outputing the clusters and labeling them 0-9.

> On Jan 23, 2014, at 10:34 PM, Tharindu Rusira <tharindurusira@gmail.com> wrote:
> 
> On Fri, Jan 24, 2014 at 9:50 AM, Angus Macnab <angus.macnab@gmail.com>wrote:
> 
>> This is a pretty classic machine learning problem and can be handled with
>> several different algorithms.  Logistic regression is the obvious choice,
>> but clustering algorithms will work fine also.  Just decompose the pixels
>> into a really long vector and train your algorithm with the input-output
>> pairs.  You can get 100% accuracy on this pretty easily if you are careful
>> with your bias-variance decomposition.  This is a fun one for neural
>> networks too!
>> 
>> Essentially any machine learning book will delve into greater detail on
>> this as the US postal digit data has been around for a long time.  I think
>> Kaggle even had this as a training exercise for a while, so there's
>> probably a ton of discussion of various methods and algorithms on their
>> message boards.
>> 
>> For kicks why don't you compare k-means clustering to logistic regression
>> using Mahout?
> Hi Angus, Chameera's requirement is to classify handwritten digits, so
> could you please explain how could K-means clustering be helpful in this
> scenario? Of course it would find different clusters but this is still a
> classification problem. Please correct me if I'm wrong.
> 
> Thanks, 
> 
> 
>> 
>> -Angus
>> 
>> 
>> 
>> 
>> On Thu, Jan 23, 2014 at 8:00 PM, Chameera Wijebandara <
>> chameerawijebandara@gmail.com> wrote:
>> 
>>> Hi,
>>> 
>>> I am trying to classify handwritten digits using mahout classification.
>> Any
>>> suggestion to come up with good solution?
>>> 
>>> --
>>> Thanks,
>>>    Chameera
> 
> 
> 
> -- 
> M.P. Tharindu Rusira Kumara
> 
> Department of Computer Science and Engineering,
> University of Moratuwa,
> Sri Lanka.
> +94757033733
> www.tharindu-rusira.blogspot.com

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