Table 13. Actural instrument flight evaluation t-test by regidence

Group	Obs	Mean	Std. Dev.	95% Conf. Interval
Seoul	30	16.495	7.016	13.875 19.115
Province	100	16.940	5.731	15.802 18.077
Diff		0.444		-2.935 2.045
diff = mean(0) - mean(1)  t = -0..353Ho: diff = 0  degrees of freedom = 128
Ha: diff < 0Pr(T<t) = 0.362		**Ha: diff != 0Pr(|T|>|t|) = 0.724		Ha: diff > 0Pr(T>t) = 0.637