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Re: st: Question about strate and stsplit
Thanks for the tip! I accidentally left the duration variable as
float, which means that some individual experienced the even in .5
year while others in .2 year. After rounding the variable, I
eliminated all the abnormal values.
On 8/10/05, Svend Juul <SJ@soci.au.dk> wrote:
> Shige asked:
> My questions is:
> 1) Is it true that _D (number of deaths) cannot be greater than _Y (time
> at risk)?
> The time at risk can be expressed in any unit, from seconds to
> centuries, and the numerical value of _Y of course depends on the unit
> Imagine 10 persons observed within a time window of one year. All 10
> died after 6 months. So _D is 10, and _Y is 5. Had you chosen days as
> the time unit, _D would still be 10, but _Y would be 1,825.
> So I don't think there is a "problem here"
> Svend Juul
> Institut for Folkesundhed, Afdeling for Epidemiologi
> (Institute of Public Health, Department of Epidemiology)
> Vennelyst Boulevard 6
> DK-8000 Aarhus C, Denmark
> Phone: +45 8942 6090
> Home: +45 8693 7796
> Email: email@example.com
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