<s>
Karaoke	B-Operating_System
Callout	I-Operating_System
is	O
a	O
karaoke	O
dueling	O
game	O
developed	O
by	O
David	O
A	O
.	O
Shamma	O
and	O
Bryan	O
Pardo	O
at	O
the	O
Interactive	O
Audio	O
Lab	O
at	O
Northwestern	O
University	O
.	O
</s>
<s>
Its	O
purpose	O
is	O
to	O
help	O
train	O
the	O
Tunebot	B-Application
database	O
by	O
providing	O
the	O
system	O
with	O
more	O
query	O
to	O
target	O
matches	O
.	O
</s>
<s>
The	O
Interactive	O
Audio	O
Lab	O
used	O
this	O
game	O
to	O
help	O
train	O
the	O
Tunebot	B-Application
engine	O
in	O
preparation	O
for	O
research	O
on	O
improving	O
the	O
search	O
engine	O
.	O
</s>
<s>
In	O
the	O
spring	O
of	O
2009	O
,	O
Karaoke	B-Operating_System
Callout	I-Operating_System
expanded	O
to	O
a	O
web-based	O
game	O
.	O
</s>
