[SciPy-Dev] t-statistic

josef.pktd@gmai... josef.pktd@gmai...
Wed Jun 12 06:36:34 CDT 2013


On Wed, Jun 12, 2013 at 6:51 AM, Sudheer Joseph
<sudheer.joseph@yahoo.com> wrote:
> Dear experts,
>
>                  I am doing a project involving
> regression of a model variable with observed variable and wanted to find t-values dynamically as the number of available observations involved
> in comparison changes. Is there a tool in numpy/scipy which gives the
> appropriate t-value if we give number of samples ?
>
> t = 2.31                # appropriate t value (where n=9, two tailed 95%)

this is the scipy-dev not the scipy-user mailing list

What are you keeping as given when you increase the sample size?

The t-value for a t-test is just a function of sqrt(n)
https://en.wikipedia.org/wiki/Student%27s_t-test#One-sample_t-test

For power and sample size calculations we keep the term without
sqrt(n) constant, which is the "effect size".
I'm using it that way in statsmodels, but the calculations are just a
line or three.

Josef
>
> with best regards,
> Sudheer
>
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