Charts of Two Sample t test

[Sidra Ilyas]

Hi Dear,

Can you please guide me how can we create charts of the outcomes of two sample t test in Stata? Two sample t tests are being run to compare the growth of different regions. Thank you

[Nick Cox]

See https://www.statalist.org/forums/for...etween-genders #2 for one suggestion.


For paired data, a quantile normal plot of the differences is appropriate.

[Sidra Ilyas]

Thanks Nick,

The post you referred is unfortunately way too complicated for me. Aren't there any Stata commands for both paired and unpaired data in this case?

Also, I am going to write a separate post as well, but if can please share your kind opinion about the following:

If there is economic growth data about two countries over the same thirty years, should it be considered as paired or unpaired data for two sample t test?

Thanks again.

[Nick Cox]

If you don't understand normal quantile plots, then you perhaps don't understand enough statistics to be using t tests in research. This is, or should be, part of a first course in statistics.

The key suggestion for unpaired data is just (after installing qplot)

sysuse auto, clear  
qplot mpg, trscale(invnormal(@)) over(foreign) aspect(1) xtitle(standard normal deviate) legend(col(1) order(2 1) pos(11) ring(0))

I will add a suggestion for paired data in the linked thread.

I will comment on your last question in the new thread,