<s>
Electronic	B-Application
markets	I-Application
(	O
or	O
electronic	O
marketplaces	O
)	O
are	O
information	O
systems	O
(	O
IS	O
)	O
which	O
are	O
used	O
by	O
multiple	O
separate	O
organizational	O
entities	O
within	O
one	O
or	O
among	O
multiple	O
tiers	O
in	O
economic	O
value	O
chains	O
.	O
</s>
<s>
a	O
monopoly	B-Application
)	O
as	O
well	O
as	O
from	O
a	O
microeconomic	O
(	O
describing	O
different	O
allocation	O
mechanisms	O
,	O
e.g.	O
</s>
<s>
public	O
auctions	O
of	O
telephone	O
frequencies	O
)	O
perspective	O
,	O
electronic	B-Application
markets	I-Application
denote	O
networked	O
forms	O
of	O
business	O
with	O
maations	O
:	O
</s>
<s>
First	O
,	O
the	O
topology	O
of	O
electronic	B-Application
markets	I-Application
may	O
be	O
centralized	O
or	O
decentralized	O
in	O
nature	O
.	O
</s>
<s>
Centralized	O
electronic	B-Application
markets	I-Application
are	O
hubs	O
which	O
often	O
provide	O
services	O
to	O
their	O
participants	O
.	O
</s>
<s>
Second	O
,	O
the	O
services	O
provided	O
by	O
electronic	B-Application
markets	I-Application
may	O
serve	O
infrastructural	O
or	O
allocation	O
purposes	O
.	O
</s>
<s>
Third	O
,	O
the	O
relationships	O
of	O
actors	O
involved	O
in	O
electronic	B-Application
markets	I-Application
may	O
be	O
stable	O
or	O
atomistic	O
in	O
nature	O
.	O
</s>
<s>
This	O
leads	O
to	O
two	O
definitions	O
:	O
In	O
a	O
narrow	O
sense	O
Electronic	B-Application
Markets	I-Application
are	O
mainly	O
conceived	O
as	O
allocation	O
platforms	O
with	O
dynamic	O
price	O
discovery	O
mechanisms	O
involving	O
atomistic	O
relationships	O
.	O
</s>
<s>
In	O
a	O
broader	O
sense	O
,	O
price	O
discovery	O
is	O
not	O
critical	O
for	O
electronic	B-Application
markets	I-Application
.	O
</s>
<s>
Electronic	B-Application
markets	I-Application
are	O
attributed	O
important	O
impacts	O
on	O
business	O
efficiencies	O
.	O
</s>
<s>
From	O
an	O
industry	O
perspective	O
,	O
transaction	O
cost	O
economics	O
were	O
used	O
to	O
illustrate	O
the	O
relationship	O
between	O
electronic	B-Application
markets	I-Application
and	O
electronic	O
hierarchies	O
.	O
</s>
<s>
While	O
the	O
former	O
are	O
in	O
line	O
with	O
the	O
narrow	O
electronic	B-Application
markets	I-Application
definition	O
,	O
the	O
latter	O
are	O
also	O
included	O
in	O
the	O
broader	O
definition	O
.	O
</s>
<s>
This	O
may	O
be	O
explained	O
since	O
in	O
reality	O
electronic	B-Application
markets	I-Application
have	O
emerged	O
as	O
platforms	O
which	O
combine	O
several	O
modes	O
of	O
governance	O
or	O
types	O
of	O
coordination	O
mechanisms	O
.	O
</s>
