st: one-sample t test query

[Gwinyai Masukume <parturitions@gmail.com>]

Hi Stata list,

I have a dataset with 32 observations (20 females and 12 males). Males
thus constitute 37.5% of the observations. Normally males should
constitute 51.5% of the observations. I want to test if the observed
37.5% males are different from 51.5%. I have issued the following
Stata command:

. ttest sex_baby = 0.515

One-sample t test
------------------------------------------------------------------------------
Variable |     Obs        Mean    Std. Err.   Std. Dev.   [95% Conf. Interval]
---------+--------------------------------------------------------------------
sex_baby |      32        .375     .086951    .4918694    .1976622    .5523378
------------------------------------------------------------------------------
    mean = mean(sex_baby)                                         t =  -1.6101
Ho: mean = 0.515                                 degrees of freedom =       31

  Ha: mean < 0.515             Ha: mean != 0.515             Ha: mean > 0.515
 Pr(T < t) = 0.0588         Pr(|T| > |t|) = 0.1175          Pr(T > t) = 0.9412

Looking at the two-tailed p-value, I conclude that 37.5% is not
significantly different from 51.5% if p < 0.05 is considered
significant.
Have I used the correct Stata command and is my interpretation correct?

Thanks,
Gwinyai
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