Table 6. Helicopter transition evaluation results evaluation
t
-test by age
Group
Obs
Mean
Sth. Dev.
95% Conf. Interval
30y below
54
89.7437
1.8468
89.239
90.247
30y above
15
85.0406
1.12668
84.416
85.664
Diff
4.703
3.2700
5.7058
diff = mean(0) - mean(1)
Ho: diff = 0
t
= 9.3608
degrees of freedom = 67
Ha: diff < 0
Pr(T<
t
) = 1.
*
Ha: diff != 0
Pr(|T|>|t|) = 0.0000
Ha: diff > 0
Pr(T>
t
) = 0.0000
p
<.05