Re: st: Re: calculating proportions

[Ekaterina Hertog <ekaterina.hertog@sociology.ox.ac.uk>]

Dear all,
Thank you very much all the advice, sorry if I appeared to abandon the 
thread, I had no internet for a week due to family illness.
I have been working through the advice that Oliver and Nick offered and 
I am most grateful to both.
I really like Nick's solution as it does not involve loops and hence 
works very quickly.
I have played a bit with the code and this is the final version which 
produces the correct rankings

sysuse auto, clear
* foreign=22 domestic=52
contract mpg foreign
relrank mpg if foreign [fw=_freq] , ref(mpg if !foreign) gen(F)
la var F "proportion of domestic cars that have lower or equal to a 
given mileage value of a foreign car"
gen negmpg = -mpg
relrank negmpg if foreign [fw=_freq] , ref(negmpg if !foreign) gen(G)
la var G "proportion of domestic cars that have higher or equal to a 
given mileage value of a foreign car"
gen H = (G+F) - 1
la var H "proportion of domestic cars that have equal mileage to a given 
mileage value of a foreign car"
replace G = G - H
replace F = F - H
l mpg F G H

Thank you very much again,
Ekaterina
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