HP (Hewlett-Packard) 40G Calculator User Manual


 
Inference aplet 9-21
Two–Sample T–Interval
Menu name T–INT: µ1 – µ2
This option uses the Student’s t–distribution to calculate a
confidence interval for the difference between the means of
two populations, µ
1
− µ
2
, when the population standard
deviations, σ
1
and σ
2
, are unknown.
Inputs The inputs are:
Results The results are:
Field name Definition
1
Sample 1 mean.
2
Sample 2 mean.
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.
x
x
Result Description
Critical T Critical value for T.
µ Min
Lower bound for µ
1
µ
2
.
µ Max
Upper bound for µ
1
µ
2
.