<s>
In	O
computational	O
learning	O
theory	O
,	O
let	O
C	O
be	O
a	O
concept	O
class	O
over	O
a	O
domain	O
X	O
and	O
c	O
be	O
a	O
concept	O
in	O
C	O
.	O
A	O
subset	O
S	O
of	O
X	O
is	O
a	O
witness	B-General_Concept
set	I-General_Concept
for	O
c	O
in	O
C	O
if	O
c(S )	O
verifies	O
c	O
(	O
i.e.	O
,	O
c	O
is	O
the	O
only	O
consistent	O
concept	O
with	O
respect	O
to	O
c(S )	O
)	O
.	O
</s>
<s>
The	O
minimum	O
size	O
of	O
a	O
witness	B-General_Concept
set	I-General_Concept
for	O
c	O
is	O
called	O
the	O
witness	O
size	O
or	O
specification	O
number	O
and	O
is	O
denoted	O
by	O
.	O
</s>
