[R] cluster with mahalanobis distance

[Phil Spector]

The manhattan distance and the Mahalanobis distances are 
quite different.  One of the main differences is that 
a covariance matrix is necessary to calculate the Mahalanobis
distance, so it's not easily accomodated by dist.  There 
is a function in base R which does calculate the Mahalanobis
distance -- mahalanobis().  So if you pass a distance matrix
calculated by mahalanobis() to the clustering function, you'll
get what you want.
 					- Phil Spector
 					 Statistical Computing Facility
 					 Department of Statistics
 					 UC Berkeley
 					 spector at stat.berkeley.edu


On Wed, 3 Mar 2010, Tal Galili wrote:

> when you create the distance function to put into the hclust, use:
>
> dist(x, method = "manhattan")
>
>
> Tal
>
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> On Wed, Mar 3, 2010 at 9:14 PM, naama <nwolf at technion.ac.il> wrote:
>
>>
>> How can I perform cluster analysis using the mahalanobis distance instead
>> of
>> the euclidean distance?
>> thank you
>> Naama Wolf
>>
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