<s>
A	O
descriptive	B-General_Concept
statistic	I-General_Concept
(	O
in	O
the	O
count	O
noun	O
sense	O
)	O
is	O
a	O
summary	O
statistic	O
that	O
quantitatively	O
describes	O
or	O
summarizes	O
features	O
from	O
a	O
collection	O
of	O
information	O
,	O
while	O
descriptive	B-General_Concept
statistics	I-General_Concept
(	O
in	O
the	O
mass	O
noun	O
sense	O
)	O
is	O
the	O
process	O
of	O
using	O
and	O
analysing	O
those	O
statistics	O
.	O
</s>
<s>
Descriptive	B-General_Concept
statistics	I-General_Concept
is	O
distinguished	O
from	O
inferential	O
statistics	O
(	O
or	O
inductive	O
statistics	O
)	O
by	O
its	O
aim	O
to	O
summarize	O
a	O
sample	O
,	O
rather	O
than	O
use	O
the	O
data	O
to	O
learn	O
about	O
the	O
population	O
that	O
the	O
sample	O
of	O
data	O
is	O
thought	O
to	O
represent	O
.	O
</s>
<s>
This	O
generally	O
means	O
that	O
descriptive	B-General_Concept
statistics	I-General_Concept
,	O
unlike	O
inferential	O
statistics	O
,	O
is	O
not	O
developed	O
on	O
the	O
basis	O
of	O
probability	O
theory	O
,	O
and	O
are	O
frequently	O
nonparametric	B-General_Concept
statistics	I-General_Concept
.	O
</s>
<s>
Even	O
when	O
a	O
data	O
analysis	O
draws	O
its	O
main	O
conclusions	O
using	O
inferential	O
statistics	O
,	O
descriptive	B-General_Concept
statistics	I-General_Concept
are	O
generally	O
also	O
presented	O
.	O
</s>
<s>
Measures	O
of	O
central	O
tendency	O
include	O
the	O
mean	O
,	O
median	O
and	O
mode	O
,	O
while	O
measures	O
of	O
variability	O
include	O
the	O
standard	B-General_Concept
deviation	I-General_Concept
(	O
or	O
variance	O
)	O
,	O
the	O
minimum	O
and	O
maximum	O
values	O
of	O
the	O
variables	O
,	O
kurtosis	B-Error_Name
and	O
skewness	B-General_Concept
.	O
</s>
<s>
Descriptive	B-General_Concept
statistics	I-General_Concept
provide	O
simple	O
summaries	O
about	O
the	O
sample	O
and	O
about	O
the	O
observations	O
that	O
have	O
been	O
made	O
.	O
</s>
<s>
For	O
example	O
,	O
the	O
shooting	O
percentage	O
in	O
basketball	B-Application
is	O
a	O
descriptive	B-General_Concept
statistic	I-General_Concept
that	O
summarizes	O
the	O
performance	O
of	O
a	O
player	O
or	O
a	O
team	O
.	O
</s>
<s>
This	O
single	O
number	O
describes	O
the	O
general	O
performance	O
of	O
a	O
student	O
across	O
the	O
range	B-General_Concept
of	O
their	O
course	O
experiences	O
.	O
</s>
<s>
More	O
recently	O
,	O
a	O
collection	O
of	O
summarisation	O
techniques	O
has	O
been	O
formulated	O
under	O
the	O
heading	O
of	O
exploratory	B-General_Concept
data	I-General_Concept
analysis	I-General_Concept
:	O
an	O
example	O
of	O
such	O
a	O
technique	O
is	O
the	O
box	B-Application
plot	I-Application
.	O
</s>
<s>
In	O
the	O
business	O
world	O
,	O
descriptive	B-General_Concept
statistics	I-General_Concept
provides	O
a	O
useful	O
summary	O
of	O
many	O
types	O
of	O
data	O
.	O
</s>
<s>
Univariate	B-General_Concept
analysis	I-General_Concept
involves	O
describing	O
the	O
distribution	O
of	O
a	O
single	O
variable	O
,	O
including	O
its	O
central	O
tendency	O
(	O
including	O
the	O
mean	O
,	O
median	O
,	O
and	O
mode	O
)	O
and	O
dispersion	O
(	O
including	O
the	O
range	B-General_Concept
and	O
quartiles	O
of	O
the	O
data-set	O
,	O
and	O
measures	O
of	O
spread	O
such	O
as	O
the	O
variance	O
and	O
standard	B-General_Concept
deviation	I-General_Concept
)	O
.	O
</s>
<s>
The	O
shape	O
of	O
the	O
distribution	O
may	O
also	O
be	O
described	O
via	O
indices	O
such	O
as	O
skewness	B-General_Concept
and	O
kurtosis	B-Error_Name
.	O
</s>
<s>
Characteristics	O
of	O
a	O
variable	O
's	O
distribution	O
may	O
also	O
be	O
depicted	O
in	O
graphical	O
or	O
tabular	O
format	O
,	O
including	O
histograms	B-Algorithm
and	O
stem-and-leaf	B-Application
display	I-Application
.	O
</s>
<s>
When	O
a	O
sample	O
consists	O
of	O
more	O
than	O
one	O
variable	O
,	O
descriptive	B-General_Concept
statistics	I-General_Concept
may	O
be	O
used	O
to	O
describe	O
the	O
relationship	O
between	O
pairs	O
of	O
variables	O
.	O
</s>
<s>
In	O
this	O
case	O
,	O
descriptive	B-General_Concept
statistics	I-General_Concept
include	O
:	O
</s>
<s>
Quantitative	O
measures	O
of	O
dependence	O
include	O
correlation	O
(	O
such	O
as	O
Pearson	O
's	O
r	O
when	O
both	O
variables	O
are	O
continuous	O
,	O
or	O
Spearman	B-General_Concept
's	I-General_Concept
rho	I-General_Concept
if	O
one	O
or	O
both	O
are	O
not	O
)	O
and	O
covariance	O
(	O
which	O
reflects	O
the	O
scale	O
variables	O
are	O
measured	O
on	O
)	O
.	O
</s>
<s>
Highly	O
skewed	B-General_Concept
data	I-General_Concept
are	O
often	O
transformed	O
by	O
taking	O
logarithms	O
.	O
</s>
