Two–Sample T–Interval
Menu name
Inputs
Results
Inference aplet
T–INT: 1 – 2
This option uses the Student's t–distribution to calculate a
confidence interval for the difference between the means of
two populations,
when the population standard
deviations,
and
, are unknown.
The inputs are:
Field name
Definition
Sample 1 mean.
x
Sample 2 mean.
x
2
s1
Sample 1 standard deviation.
s2
Sample 2 standard deviation.
n1
Sample 1 size.
n2
Sample 2 size.
C
Confidence level.
_Pooled
Whether or not to pool the samples based
on their standard deviations.
The results are:
Result
Description
Critical T
Critical value for T.
Lower bound for
Min
Upper bound for
Max
–
.
1
2
–
.
1
2
9-21