<s>
Multi	B-Algorithm
Expression	I-Algorithm
Programming	I-Algorithm
(	O
MEP	O
)	O
is	O
an	O
evolutionary	O
algorithm	O
for	O
generating	O
mathematical	O
functions	O
describing	O
a	O
given	O
set	O
of	O
data	O
.	O
</s>
<s>
MEP	O
is	O
a	O
Genetic	B-Algorithm
Programming	I-Algorithm
variant	O
encoding	O
multiple	O
solutions	O
in	O
the	O
same	O
chromosome	O
.	O
</s>
<s>
This	O
representation	O
was	O
inspired	O
by	O
Three-address	B-Application
code	I-Application
.	O
</s>
<s>
For	O
most	O
of	O
the	O
problems	O
this	O
advantage	O
comes	O
with	O
no	O
running-time	O
penalty	O
compared	O
with	O
genetic	B-Algorithm
programming	I-Algorithm
variants	O
encoding	O
a	O
single	O
solution	O
in	O
a	O
chromosome	O
.	O
</s>
<s>
MEP	O
chromosomes	O
are	O
arrays	O
of	O
instructions	O
represented	O
in	O
Three-address	B-Application
code	I-Application
format	O
.	O
</s>
<s>
For	O
instance	O
,	O
in	O
the	O
case	O
of	O
symbolic	B-Algorithm
regression	I-Algorithm
,	O
the	O
fitness	O
is	O
the	O
sum	O
of	O
differences	O
(	O
in	O
absolute	O
value	O
)	O
between	O
the	O
expected	O
output	O
(	O
called	O
target	O
)	O
and	O
the	O
actual	O
output	O
.	O
</s>
<s>
This	O
is	O
different	O
from	O
other	O
GP	O
techniques	O
:	O
In	O
Linear	B-Algorithm
genetic	I-Algorithm
programming	I-Algorithm
the	O
last	O
instruction	O
will	O
give	O
the	O
output	O
.	O
</s>
<s>
In	O
Cartesian	B-Algorithm
Genetic	I-Algorithm
Programming	I-Algorithm
the	O
gene	O
providing	O
the	O
output	O
is	O
evolved	O
like	O
all	O
other	O
genes	O
.	O
</s>
<s>
It	O
can	O
be	O
used	O
for	O
data	O
analysis	O
,	O
particularly	O
for	O
solving	O
symbolic	B-Algorithm
regression	I-Algorithm
,	O
statistical	B-General_Concept
classification	I-General_Concept
and	O
time-series	O
problems	O
.	O
</s>
<s>
is	O
a	O
free	O
and	O
open	O
source	O
library	O
implementing	O
Multi	B-Algorithm
Expression	I-Algorithm
Programming	I-Algorithm
technique	O
.	O
</s>
<s>
is	O
a	O
new	O
open	O
source	O
library	O
implementing	O
Multi	B-Algorithm
Expression	I-Algorithm
Programming	I-Algorithm
technique	O
in	O
Haskell	O
programming	O
language	O
.	O
</s>
