Casio fx-9860G SD User Manual page 344

o
.................................. mean of sample
x
............................. sample standard deviation (
n
-1
n
.................................. size of sample (positive integer)
After setting all the parameters, use c to move the highlighting to "Execute" and then press
the function key shown below to perform the calculation.
• 1(CALC) ... Performs the calculation.
Calculation Result Output Example
Left .............................. confidence interval lower limit (left edge)
Right ............................ confidence interval upper limit (right edge)
o
.................................. mean of sample
x
............................. sample standard deviation
n
-1
n
.................................. size of sample
u u u u u 2-Sample t
Interval
t
2-Sample Interval calculates the confidence interval for the difference between two
population means when both population standard deviations are unknown. The
t
applied to distribution.
The following confidence interval applies when pooling is in effect.
The value 100 (1 – ) % is the confidence level.
Left = (o
Right = (o
x =
p n–1
6-6-9
Confidence Interval
– o
)– t x
–2
1 2 n +n
2
1 2
– o
)+ t
1 2 n +n –2
2
1 2
(n –1)x +(n –1)x
2
1 1 2
n–1
n + n – 2
1 2
20050401
x > 0)
n
-1
is the level of significance.
1 + 1
2
n n
p n–1
1 2
1 + 1
x
2
n n
p n–1
1 2
2
2
n–1
t
interval is