Casio CFX-9850G PLUS, User'S Manual & Technical Reference

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ˆp
1
.................... estimated sample propotion for sample 1
ˆp
2
.................... estimated sample propotion for sample 2
n
1
.................... sample 1 size
n
2
.................... sample 2 size
k k
k k k
t
Confidence Interval
You can use the following menu to select from two types of
t
confidence interval.
• {
1-S
}
/
{
2-S
} ... {1-Sample}/{2-Sample}
t
Interval
u u
u u u
1-Sample
t
Interval
1-Sample
t
Interval
calculates the confidence interval for an unknown population
mean when the population standard deviation is unknown.
The following is the confidence interval. The value 100 (1 –
α
) % is the confidence
level.
Left =
o
– t
n
– 1
α
2
Right
=
o
+
t
n – 1
α
2
x
n
–1
σ
n
x
n
–1
σ
n
Perform the following key operations from the statistical data list.
4
(INTR)
2
(
t
)
1
(1-S)
The following shows the meaning of each item in the case of list data specifica-
tion.
Data ................ data type
C-Level ........... confidence level (0
<
C-Level < 1)
List .................. list whose contents you want to use as sample data
Freq ................ sample frequency
Execute .......... execute a calculation
The following shows the meaning of parameter data specification items that are
different from list data specification.
o
..................... sample mean
x
σ
n -1
................ sample standard deviation (
x
σ
n -1
>
0)
n
..................... sample size (positive integer)
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Confidence Interval