Casio fx-9860G AU PLUS, User Manual

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20050401
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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 –1
2
+( n
2
–1) x
2 n –1
2
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)
6-5-13
Tests
o
1
: mean of sample 1
o
2
: mean of sample 2
x
1
σ
n -1
: standard deviation of
sample 1
x
2
σ
n
-1
: standard deviation of
sample 2
n
1
: size of sample 1
n
2
: size of sample 2
x
p
σ
n -1
: pooled sample standard
deviation
df
: degrees of freedom
o
1
: mean of sample 1
o
2
: mean of sample 2
x
1
σ
n -1
: standard deviation of
sample 1
x
2
σ
n -1
: standard deviation of
sample 2
n
1
: size of sample 1
n
2
: size of sample 2
df
: degrees of freedom