Casio FX-9750G PLUS User's Manual & Technical Reference page 313

u u u u u 2-Sample t Test
t
2-Sample Test compares the population means when the population standard
deviations are unknown. The 2-Sample
The following applies when pooling is in effect.
– o
o
1 2
t =
1 +
σ
x
2
n
p n–1
1
(n –1)x
σ
= 1
x
p n–1
df n n
= + – 2
1 2
The following applies when pooling is not in effect.
– o
o
1 2
t =
σ σ
x x
2
1 n–1 + 2 n–1
n n
1 2
1
df =
2
(1–C )
C
+
–1 –1
n n
1 2
σ
x
2
1 n–1
n
1
C =
σ σ
x x
2
1 n–1 + 2 n–1
n n
1
Perform the following key operations from the statistical data list.
3(TEST)
t
)
2(
2(2-S)
t
Test is applied to
1
n
2
σ σ
+(n –1)x
2
1 n–1 2 2 n –1
+ n – 2
n
1 2
2
2
2
2
t
-distribution.
o : sample 1 mean
1
o : sample 2 mean
2
σ
x
: sample 1 standard
1 n -1
deviation
σ
x
: sample 2 standard
2 n -1
2
deviation
n
: sample 1 size
1
n
: sample 2 size
2
σ
x
: pooled sample standard
p n
-1
deviation
df
: degrees of freedom
: sample 1 mean
o
1
o : sample 2 mean
2
x σ
: sample 1 standard
1 n -1
deviation
σ
x
: sample 2 standard
2 n -1
deviation
n
: sample 1 size
1
n
: sample 2 size
2
df
: degrees of freedom
18 - 6
Tests
285