Texas Instruments TI-82 STATS Manual Book page 268

Distribution Functions
normalcdf(
invNorm(
tpdf(
13–30 Inferential Statistics and Distributions
(continued)
computes the normal distribution probability
normalcdf(
between lowerbound and upperbound for the specified mean
and standard deviation
and =1.
s
lowerbound
normalcdf(
computes the inverse cumulative normal distribution
invNorm(
function for a given area under the normal distribution curve
specified by mean
m
value associated with an area to the left of the x value.
0  area  1 must be true. The defaults are
area[ ]
m s
invNorm( , ,
computes the probability density function (pdf) for the
tpdf(
Student-t distribution at a specified x value. df (degrees of
freedom) must be >0. To plot the Student-t distribution, paste
to the editor. The probability density function (pdf) is:
tpdf( Y=
[( df 1 2 ) ]
f x ( )
( df / 2 )
x df
tpdf( , )
. The defaults are
s
upperbound[
m
, ,
and standard deviation
)
/ ( 1 x df 2 / )
df
Note: For this example,
Xmin = L4.5
Xmax = 4.5
Ymin = 0
Ymax = .4
=0
m
]
s
, )
. It calculates the x
s
=0 and =1.
m s
( df 1 2 ) /
m