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bodhisattwa-chakraborty / dmfa07

Automatically exported from code.google.com/p/dmfa07
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DBSCAN.M boundary points propagate group membership #3

Open GoogleCodeExporter opened 8 years ago

GoogleCodeExporter commented 8 years ago 
Suppose we have the vector

y = [1 1 1 2 3 4]

Then, with eps = 1 and k = 4 we clearly expect that 3 to be on the boundary of 
the group formed by [1 1 1 2]. By algorithm definition, 3 is not allowed to 
propagate group membership. However, we find that

>> [a,b] = dbscan(y', 3, 1)

a =

     1     1     1     1     1     1

b =

     1     1     1     1     0     0

where 3 did propagate the group membership to 4. 4 However should be classified 
as an outlier. (Note that I entered k-1 to dbscan, as explained in my other bug 
report.

Original issue reported on code.google.com by fre...@googlemail.com on 29 Nov 2012 at 3:35