<s>
Multiple	B-General_Concept
Discriminant	I-General_Concept
Analysis	I-General_Concept
(	O
MDA	O
)	O
is	O
a	O
multivariate	O
dimensionality	B-Algorithm
reduction	I-Algorithm
technique	O
.	O
</s>
<s>
MDA	O
is	O
not	O
directly	O
used	O
to	O
perform	O
classification	B-General_Concept
.	O
</s>
<s>
It	O
merely	O
supports	O
classification	B-General_Concept
by	O
yielding	O
a	O
compressed	B-General_Concept
signal	I-General_Concept
amenable	O
to	O
classification	B-General_Concept
.	O
</s>
<s>
MDA	O
is	O
useful	O
because	O
most	O
classifiers	B-General_Concept
are	O
strongly	O
affected	O
by	O
the	O
curse	B-Algorithm
of	I-Algorithm
dimensionality	I-Algorithm
.	O
</s>
<s>
In	O
other	O
words	O
,	O
when	O
signals	O
are	O
represented	O
in	O
very-high-dimensional	O
spaces	O
,	O
the	O
classifier	B-General_Concept
's	O
performance	O
is	O
catastrophically	O
impaired	O
by	O
the	O
overfitting	B-Error_Name
problem	O
.	O
</s>
