Dear Stata list,
I would like to double check the interpretation and appropriateness of
the following statistical test I performed.
My alternate hypothesis is that, ?There is a difference in the baby?s
mode of delivery depending on maternal age? And the null hypothesis is
that, ?There is no difference in the baby?s mode of delivery depending
on maternal age?
Looking at the output ?Ha: diff != 0, Pr(|T| > |t|) = 0.4861?, I
fail to reject the null hypothesis and conclude that, ?There is no
difference in the baby?s mode of delivery depending on maternal age?
Is this a sound and appropriate interpretation?
. *** Doing a T-test
. ttest age, by(mode_delivery)
Two-sample t test with equal variances
------------------------------------------------------------------------------
Group | Obs Mean Std.
Err. Std. Dev. [95% Conf. Interval]
---------+--------------------------------------------------------------------
Vaginal
| 166 28.83072 .4696729 6.051313 27.90338 29.75807
C/sectio | 84 29.39524 .6579862 6.030543 28.08653 30.70395
---------+--------------------------------------------------------------------
combined | 250 29.0204 .3818851 6.038134 28.26826 29.77254
---------+--------------------------------------------------------------------
diff
| -.5645152 .8093331 -2.158558 1.029528
------------------------------------------------------------------------------
diff = mean(Vaginal) -
mean(C/sectio) t = -0.6975
Ho: diff = 0 degrees of freedom = 248
Ha: diff < 0 Ha: diff != 0 Ha: diff > 0
Pr(T < t) = 0.2431 Pr(|T| > |t|) =
0.4861 Pr(T > t) = 0.7569
With kind regards,
Gwinyai
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