<s>
Parametric	B-General_Concept
statistics	I-General_Concept
is	O
a	O
branch	O
of	O
statistics	O
which	O
assumes	O
that	O
sample	O
data	O
comes	O
from	O
a	O
population	O
that	O
can	O
be	O
adequately	O
modeled	O
by	O
a	O
probability	O
distribution	O
that	O
has	O
a	O
fixed	O
set	O
of	O
parameters	O
.	O
</s>
<s>
Conversely	O
a	O
non-parametric	B-General_Concept
model	I-General_Concept
does	O
not	O
assume	O
an	O
explicit	O
(	O
finite-parametric	O
)	O
mathematical	O
form	O
for	O
the	O
distribution	O
when	O
modeling	O
the	O
data	O
.	O
</s>
<s>
Regarding	O
nonparametric	B-General_Concept
(	O
and	O
semiparametric	O
)	O
models	O
,	O
Sir	O
David	O
Cox	O
has	O
said	O
,	O
"	O
These	O
typically	O
involve	O
fewer	O
assumptions	O
of	O
structure	O
and	O
distributional	O
form	O
but	O
usually	O
contain	O
strong	O
assumptions	O
about	O
independencies	O
"	O
.	O
</s>
<s>
The	O
normal	O
family	O
of	O
distributions	O
all	O
have	O
the	O
same	O
general	O
shape	O
and	O
are	O
parameterized	O
by	O
mean	O
and	O
standard	B-General_Concept
deviation	I-General_Concept
.	O
</s>
<s>
That	O
means	O
that	O
if	O
the	O
mean	O
and	O
standard	B-General_Concept
deviation	I-General_Concept
are	O
known	O
and	O
if	O
the	O
distribution	O
is	O
normal	O
,	O
the	O
probability	O
of	O
any	O
future	O
observation	O
lying	O
in	O
a	O
given	O
range	O
is	O
known	O
.	O
</s>
<s>
Suppose	O
that	O
we	O
have	O
a	O
sample	O
of	O
99	O
test	O
scores	O
with	O
a	O
mean	O
of	O
100	O
and	O
a	O
standard	B-General_Concept
deviation	I-General_Concept
of	O
1	O
.	O
</s>
<s>
If	O
we	O
assume	O
all	O
99	O
test	O
scores	O
are	O
random	O
observations	O
from	O
a	O
normal	O
distribution	O
,	O
then	O
we	O
predict	O
there	O
is	O
a	O
1%	O
chance	O
that	O
the	O
100th	O
test	O
score	O
will	O
be	O
higher	O
than	O
102.33	O
(	O
that	O
is	O
,	O
the	O
mean	O
plus	O
2.33	O
standard	B-General_Concept
deviations	I-General_Concept
)	O
,	O
assuming	O
that	O
the	O
100th	O
test	O
score	O
comes	O
from	O
the	O
same	O
distribution	O
as	O
the	O
others	O
.	O
</s>
<s>
A	O
non-parametric	B-General_Concept
estimate	O
of	O
the	O
same	O
thing	O
is	O
the	O
maximum	O
of	O
the	O
first	O
99	O
scores	O
.	O
</s>
<s>
Parametric	B-General_Concept
statistics	I-General_Concept
was	O
mentioned	O
by	O
R	O
.	O
A	O
.	O
Fisher	O
in	O
his	O
work	O
Statistical	O
Methods	O
for	O
Research	O
Workers	O
in	O
1925	O
,	O
which	O
created	O
the	O
foundation	O
for	O
modern	O
statistics	O
.	O
</s>
