Raoul:
Your hunch seems to be correct:
sysuse auto, clear
sum price
gen price2 = price - r(mean)
gen double price3 = price - r(mean)
sum price2 price3
However note that the difference in the highest and lowest price is aprox. 1,200 dollar and that price2 is different from zero in only the fifth decimal place, so I would consider that zero for any practical application.
HTH,
Maarten
-----------------------------------------
Maarten L. Buis
Department of Social Research Methodology
Vrije Universiteit Amsterdam
Boelelaan 1081
1081 HV Amsterdam
The Netherlands
visiting adress:
Buitenveldertselaan 3 (Metropolitan), room Z214
+31 20 5986715
http://home.fsw.vu.nl/m.buis/
-----------------------------------------
> -----Original Message-----
> From: owner-statalist@hsphsun2.harvard.edu [mailto:owner-statalist@hsphsun2.harvard.edu]On Behalf Of Raoul C Reulen
> Sent: vrijdag 25 november 2005 9:43
> To: statalist@hsphsun2.harvard.edu
> Subject: st: variable mean and r(mean), why do they differ?
>
> If I want to save the mean of a variable into a new variable, I would first:
> sum var1
> gen var2, r(mean)
> But if I subtract var1-var2, the outcome is almost, but not exactly "0". How can make sure that both means are equal?
> I have tried .round, .int. , but that doesn't work. Do I have to change the storage type? Thanks for the advice.
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