greater or equal not working with 2 decimals

[Emilio Herrerias]

Hello!

I am trying to create a categorical variable (Y/N) when another variable measuring proportions is greater than or equal to 0.96, using operator "=>". However, Stata only marks proportions that are greater than 0.96, skipping those that are equal to 0.96:

clear
set obs 1000
set seed 2

* cutoff with 2 decimals:

gen rand_2decimals = runiformint(0, 100)/100
gen atorabove96 = "Y" if rand_2decimals >=.96
sort rand_2decimals

* Notice 8 observations with value 0.96 that were not marked "Y".


*I also found that this problem does not appear when using more decimals (using 7 decimals below):

* cutoff with more decimals:

gen rand_moredec = runiform()
gen atorabove96_more = "Y" if rand_moredec >=.96
sort rand_moredec

* I can even create another categorical variable from a cutoff to 7 decimals, and Stata will correctly include the case with a value exactly equal to the cutoff:
gen cutoff="y" if rand_moredec>= .9609721

Can someone explain why Stata does not recognize >=0.96, or tell me where my error is?

[Joseph Coveney]

Can someone explain why Stata does not recognize >=0.96, or tell me where my error is?

Use a display format that shows more decimals, say,

format rand_2decimals %010.8f

and you'll see that Stata is correct.

[Joseph Coveney]

Oh, I forgot to mention: if you're wondering about why you didn't get exactly 0.96, see help precision.