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

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u u
u u
u
2-Sample t Test
2-Sample
t
Test compares the population means when the population standard
deviations are unknown. The 2-Sample
t
Test is applied to
t
-distribution.
The following applies when pooling is in effect.
t
=
o
1
–
o
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
–12
+(
n
2
–1)
x
2
n
–12
σ σ
df
=
n
1
+
n
2
– 2
The following applies when pooling is not in effect.
t
=
o
1
–
o
2
x
1 n –1
2
σ
n
1
+
x
2 n –1
2
σ
n
2
df
=
1
C
2
n
1
–1
+
(1–
C
)
2
n
2
–1
C
=
x
1
n
–1
2
σ
n
1
+
x
2
n
–1
2
σ
n
2
x
1 n –1
2
σ
n
1
Perform the following key operations from the statistical data list.
3
(TEST)
2
(
t
)
2
(2-S)
Tests
18 - 6
o
1
: sample 1 mean
o
2
: sample 2 mean
x
1
σ
n -1
: sample 1 standard
deviation
x
2
σ
n -1
: sample 2 standard
deviation
n
1
: sample 1 size
n
2
: sample 2 size
x
p
σ
n -1
: pooled sample standard
deviation
df
: degrees of freedom
o
1
: sample 1 mean
o
2
: sample 2 mean
x
1
σ
n -1
: sample 1 standard
deviation
x
2
σ
n -1
: sample 2 standard
deviation
n
1
: sample 1 size
n
2
: sample 2 size
df
: degrees of freedom