Casio CFX-9850GB PLUS, Руководство пользователя

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20070201
¯ x
................................... mean of sample
x
σ
n
-1
............................. sample standard deviation (
x
σ
n
-1
>
0)
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 ............................... confi dence interval lower limit (left edge)
Right ............................. confi dence interval upper limit (right edge)
o
................................... mean of sample
x
σ
n
-1
............................. sample standard deviation
n
.................................. size of sample
u 2-Sample
t
Interval
2-Sample
t
Interval calculates the confi dence interval for the difference between two
population means when both population standard deviations are unknown. The
t
interval is
applied to
t
distribution.
The following confi dence interval applies when pooling is in effect.
α
is the level of
signifi cance. The value 100 (1 –
α
) % is the confi dence level.
Left = (
o
1
–
o
2
) – t
α
2
Right = (
o
1
–
o
2
) + t
α
2
n
1
+ n
2
–2 n
1
1
+
n
2
1
x
p n –1
2
σ
n
1
+ n
2
–2 n
1
1
+
n
2
1
x
p n –1
2
σ
Left = (
o
1
–
o
2
) – t
α
2
Right = (
o
1
–
o
2
) + t
α
2
n
1
+ n
2
–2 n
1
1
+
n
2
1
x
p n –1
2
σ
n
1
+ n
2
–2 n
1
1
+
n
2
1
x
p n –1
2
σ
x
p n –1
=
σ
n
1
+ n
2
– 2
( n
1
–1) x
1 n –1
2
+( n
2
–1) x
2 n –1
2
σ σ
x
p n –1
=
σ
n
1
+ n
2
– 2
( n
1
–1) x
1 n –1
2
+( n
2
–1) x
2 n –1
2
σ σ
6-6-9
Confi dence Interval