<s>
In	O
computer	B-General_Concept
science	I-General_Concept
,	O
learning	B-Algorithm
vector	I-Algorithm
quantization	I-Algorithm
(	O
LVQ	B-Algorithm
)	O
is	O
a	O
prototype-based	B-Application
supervised	B-General_Concept
classification	I-General_Concept
algorithm	O
.	O
</s>
<s>
LVQ	B-Algorithm
is	O
the	O
supervised	B-General_Concept
counterpart	O
of	O
vector	B-Algorithm
quantization	I-Algorithm
systems	O
.	O
</s>
<s>
LVQ	B-Algorithm
can	O
be	O
understood	O
as	O
a	O
special	O
case	O
of	O
an	O
artificial	B-Architecture
neural	I-Architecture
network	I-Architecture
,	O
more	O
precisely	O
,	O
it	O
applies	O
a	O
winner-take-all	B-Algorithm
Hebbian	O
learning-based	O
approach	O
.	O
</s>
<s>
It	O
is	O
a	O
precursor	O
to	O
self-organizing	B-Algorithm
maps	I-Algorithm
(	O
SOM	O
)	O
and	O
related	O
to	O
neural	B-Algorithm
gas	I-Algorithm
,	O
and	O
to	O
the	O
k-nearest	B-General_Concept
neighbor	I-General_Concept
algorithm	I-General_Concept
(	O
k-NN	B-General_Concept
)	O
.	O
</s>
<s>
LVQ	B-Algorithm
was	O
invented	O
by	O
Teuvo	O
Kohonen	B-Algorithm
.	O
</s>
<s>
An	O
LVQ	B-Algorithm
system	O
is	O
represented	O
by	O
prototypes	B-Application
which	O
are	O
defined	O
in	O
the	O
feature	O
space	O
of	O
observed	O
data	O
.	O
</s>
<s>
In	O
winner-take-all	B-Algorithm
training	O
algorithms	O
one	O
determines	O
,	O
for	O
each	O
data	O
point	O
,	O
the	O
prototype	B-Application
which	O
is	O
closest	O
to	O
the	O
input	O
according	O
to	O
a	O
given	O
distance	O
measure	O
.	O
</s>
<s>
The	O
position	O
of	O
this	O
so-called	O
winner	O
prototype	B-Application
is	O
then	O
adapted	O
,	O
i.e.	O
</s>
<s>
An	O
advantage	O
of	O
LVQ	B-Algorithm
is	O
that	O
it	O
creates	O
prototypes	B-Application
that	O
are	O
easy	O
to	O
interpret	O
for	O
experts	O
in	O
the	O
respective	O
application	O
domain	O
.	O
</s>
<s>
LVQ	B-Algorithm
systems	O
can	O
be	O
applied	O
to	O
multi-class	B-General_Concept
classification	I-General_Concept
problems	O
in	O
a	O
natural	O
way	O
.	O
</s>
<s>
A	O
key	O
issue	O
in	O
LVQ	B-Algorithm
is	O
the	O
choice	O
of	O
an	O
appropriate	O
measure	O
of	O
distance	O
or	O
similarity	O
for	O
training	O
and	O
classification	B-General_Concept
.	O
</s>
<s>
LVQ	B-Algorithm
can	O
be	O
a	O
source	O
of	O
great	O
help	O
in	O
classifying	O
text	O
documents	O
.	O
</s>
