<s>
PropBank	B-General_Concept
is	O
a	O
corpus	O
that	O
is	O
annotated	O
with	O
verbal	O
propositions	O
and	O
their	O
argumentsa	O
"	O
proposition	O
bank	O
"	O
.	O
</s>
<s>
Although	O
"	O
PropBank	B-General_Concept
"	O
refers	O
to	O
a	O
specific	O
corpus	O
produced	O
by	O
Martha	O
Palmer	O
et	O
al.	O
,	O
the	O
term	O
propbank	B-General_Concept
is	O
also	O
coming	O
to	O
be	O
used	O
as	O
a	O
common	O
noun	O
referring	O
to	O
any	O
corpus	O
that	O
has	O
been	O
annotated	O
with	O
propositions	O
and	O
their	O
arguments	O
.	O
</s>
<s>
The	O
PropBank	B-General_Concept
project	O
has	O
played	O
a	O
role	O
in	O
recent	O
research	O
in	O
natural	B-Language
language	I-Language
processing	I-Language
,	O
and	O
has	O
been	O
used	O
in	O
semantic	O
role	O
labelling	O
.	O
</s>
<s>
PropBank	B-General_Concept
differs	O
from	O
FrameNet	B-General_Concept
,	O
the	O
resource	O
to	O
which	O
it	O
is	O
most	O
frequently	O
compared	O
,	O
in	O
several	O
ways	O
.	O
</s>
<s>
PropBank	B-General_Concept
is	O
a	O
verb-oriented	O
resource	O
,	O
while	O
FrameNet	B-General_Concept
is	O
centered	O
on	O
the	O
more	O
abstract	O
notion	O
of	O
frames	O
,	O
which	O
generalizes	O
descriptions	O
across	O
similar	O
verbs	O
(	O
e.g.	O
</s>
<s>
PropBank	B-General_Concept
does	O
not	O
annotate	O
events	O
or	O
states	O
of	O
affairs	O
described	O
using	O
nouns	O
.	O
</s>
<s>
PropBank	B-General_Concept
commits	O
to	O
annotating	O
all	O
verbs	O
in	O
a	O
corpus	O
,	O
whereas	O
the	O
FrameNet	B-General_Concept
project	O
chooses	O
sets	O
of	O
example	O
sentences	O
from	O
a	O
large	O
corpus	O
and	O
only	O
in	O
a	O
few	O
cases	O
has	O
annotated	O
longer	O
continuous	O
stretches	O
of	O
text	O
.	O
</s>
<s>
PropBank-style	O
annotations	O
often	O
remain	O
close	O
to	O
the	O
syntactic	O
level	O
,	O
while	O
FrameNet-style	O
annotations	O
are	O
sometimes	O
more	O
semantically	O
motivated	O
.	O
</s>
<s>
From	O
the	O
start	O
,	O
PropBank	B-General_Concept
was	O
developed	O
with	O
the	O
idea	O
of	O
serving	O
as	O
training	O
data	O
for	O
machine	O
learning-based	O
semantic	O
role	O
labeling	O
systems	O
in	O
mind	O
.	O
</s>
<s>
Due	O
to	O
such	O
differences	O
,	O
semantic	O
role	O
labeling	O
with	O
respect	O
to	O
PropBank	B-General_Concept
is	O
often	O
a	O
somewhat	O
easier	O
task	O
than	O
producing	O
FrameNet-style	O
annotations	O
.	O
</s>
