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
chosen.
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
__________________________________________
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 protected]
__________________________________________
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