<s>
The	O
Greenwood	B-General_Concept
statistic	I-General_Concept
is	O
a	O
spacing	O
statistic	O
and	O
can	O
be	O
used	O
to	O
evaluate	O
clustering	O
of	O
events	O
in	O
time	O
or	O
locations	O
in	O
space	O
.	O
</s>
<s>
Where	O
intervals	O
are	O
given	O
by	O
numbers	O
that	O
do	O
not	O
represent	O
a	O
fraction	O
of	O
the	O
time	O
period	O
or	O
distance	O
,	O
the	O
Greenwood	B-General_Concept
statistic	I-General_Concept
is	O
modified	O
and	O
is	O
given	O
by	O
:	O
</s>
<s>
The	O
Greenwood	B-General_Concept
statistic	I-General_Concept
is	O
a	O
comparative	O
measure	O
that	O
has	O
a	O
range	O
of	O
values	O
between	O
0	O
and	O
1	O
.	O
</s>
<s>
For	O
example	O
,	O
applying	O
the	O
Greenwood	B-General_Concept
statistic	I-General_Concept
to	O
the	O
arrival	O
of	O
11	O
buses	O
in	O
a	O
given	O
time	O
period	O
of	O
say	O
1	O
hour	O
,	O
where	O
in	O
the	O
first	O
example	O
all	O
eleven	O
buses	O
arrived	O
at	O
a	O
given	O
point	O
each	O
6	O
minutes	O
apart	O
,	O
would	O
give	O
a	O
result	O
of	O
roughly	O
0.10	O
.	O
</s>
<s>
So	O
this	O
can	O
be	O
used	O
to	O
tell	O
how	O
well	O
a	O
bus	O
system	O
is	O
running	O
and	O
in	O
a	O
similar	O
way	O
,	O
the	O
Greenwood	B-General_Concept
statistic	I-General_Concept
was	O
also	O
used	O
to	O
determine	O
how	O
and	O
where	O
genes	O
are	O
placed	O
in	O
the	O
chromosomes	O
of	O
living	O
organisms	O
.	O
</s>
