# Inferences Concerning One Variance - HP 50g User Manual

Graphing calculator.

Thus, we accept (more accurately, we do not reject) the hypothesis: H
, or H
:
, against the alternative hypothesis H
0
The test t value is t = -1.341776, with a P-value = 0.09130961, and critical t is
–t = -1.659782. The graphical results are:
These three examples should be enough to understand the operation of the
hypothesis testing pre-programmed feature in the calculator.

## Inferences concerning one variance

The null hypothesis to be tested is , H
)100%, or significance level , using a sample of size n, and variance s
test statistic to be used is a chi-squared test statistic defined as
Depending on the alternative hypothesis chosen, the P-value is calculated as
follows:
2
H
:
<
1
o
2
H
:
>
1
o
2
H
:
1
o
where the function min[x,y] produces the minimum value of x or y (similarly,
max[x,y] produces the maximum value of x or y). UTPC( ,x) represents the
calculator's upper-tail probabilities for
2
,
P-value = P(
2
,
P-value = P(
2
,
P-value =2 min[P(
2 min[1-UTPC( ,
2
2
:
=
, at a level of confidence (1-
o
o
2
(
n
) 1
s
2
o
2
0
2
2
<
) = 1-UTPC( ,
o
2
2
>
) = UTPC( ,
o
2
2
<
o
2
), UTPC( ,
o
= n - 1 degrees of freedom.
:
< , or H
1
2
)
o
2
)
o
2
2
), P(
>
)] =
o
2
)]
o
:
=
0
:
.
1
2
. The
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