User's Manual

13-32 Inferential Statistics and Distributions
8313INFE.DOC TI-83 international English Bob Fedorisko Revised: 02/19/01 12:47 PM Printed: 02/19/01 1:38 PM
Page 32 of 36
Ü
pdf(
computes the probability density function (pdf) for
the
Û
distribution at a specified
x
value.
numerator df
(degrees of freedom) and
denominator df
must be integers
> 0. To plot the
Û
distribution, paste
Ü
pdf(
to the
Y=
editor.
The probability density function (pdf) is:
fx
nd
nd
n
d
xnxd x
n
nnd
()
[( ) ]
()()
()
()
=
+






+≥
−−+
Γ
ΓΓ
/
//
/,
/
//
2
22
10
2
21 2
where
n
= numerator degrees of freedom
d
= denominator degrees of freedom
Ü
pdf(
x
,
numerator df
,
denominator df
)
Note:
For this example,
Xmin = 0
Xmax = 5
Ymin = 0
Ymax = 1
Ü
cdf(
computes the
Û
distribution probability between
lowerbound
and
upperbound
for the specified
numerator
df
(degrees of freedom) and
denominator df
.
numerator
df
and
denominator df
must be integers >0.
Ü
cdf(
lowerbound
,
upperbound
,
numerator df
,
denominator df
)
Ü
pdf(
Ü
cdf(