<s>
In	O
statistics	O
and	O
data	B-General_Concept
analysis	I-General_Concept
the	O
application	B-Application
software	I-Application
CumFreq	B-Algorithm
is	O
a	O
tool	O
for	O
cumulative	O
frequency	O
analysis	O
of	O
a	O
single	B-General_Concept
variable	I-General_Concept
and	O
for	O
probability	O
distribution	O
fitting	O
.	O
</s>
<s>
CumFreq	B-Algorithm
uses	O
the	O
plotting	O
position	O
approach	O
to	O
estimate	O
the	O
cumulative	O
frequency	O
of	O
each	O
of	O
the	O
observed	O
magnitudes	O
in	O
a	O
data	O
series	O
of	O
the	O
variable	O
.	O
</s>
<s>
Another	O
characteristic	O
of	O
CumFreq	B-Algorithm
is	O
that	O
it	O
provides	O
the	O
option	O
to	O
use	O
two	O
different	O
probability	O
distributions	O
,	O
one	O
for	O
the	O
lower	O
data	O
range	O
,	O
and	O
one	O
for	O
the	O
higher	O
.	O
</s>
<s>
During	O
the	O
input	O
phase	O
,	O
the	O
user	O
can	O
select	O
the	O
number	O
of	O
intervals	O
needed	O
to	O
determine	O
the	O
histogram	B-Algorithm
.	O
</s>
<s>
The	O
output	O
section	O
provides	O
a	O
calculator	O
to	O
facilitate	O
interpolation	B-Algorithm
and	O
extrapolation	O
.	O
</s>
<s>
Further	O
it	O
gives	O
the	O
option	O
to	O
see	O
the	O
Q	B-Application
–	I-Application
Q	I-Application
plot	I-Application
in	O
terms	O
of	O
calculated	O
and	O
observed	O
cumulative	O
frequencies	O
.	O
</s>
<s>
The	O
program	O
can	O
produce	O
generalizations	O
of	O
the	O
normal	O
,	O
logistic	O
,	O
and	O
other	O
distributions	O
by	O
transforming	O
the	O
data	O
using	O
an	O
exponent	O
that	O
is	O
optimized	O
to	O
obtain	O
the	O
best	B-Algorithm
fit	I-Algorithm
.	O
</s>
<s>
CumFreq	B-Algorithm
makes	O
use	O
of	O
that	O
opportunity	O
.	O
</s>
<s>
Cumfreq	B-Algorithm
produces	O
a	O
list	O
of	O
distributions	O
ranked	O
by	O
goodness	O
of	O
fit	O
.	O
</s>
<s>
From	O
the	O
cumulative	O
distribution	O
function	O
(	O
CDF	O
)	O
one	O
can	O
derive	O
a	O
histogram	B-Algorithm
and	O
the	O
probability	O
density	O
function	O
(	O
PDF	O
)	O
.	O
</s>
