Dave wrote:
I am undertaking some survival analysis and want to derive a two-tailed
p-value for each record in the data. Example data:
Sex Age group Observed Expected .. Poisson(two-tailed)
MALE 0-4 years 4 0.05 .. ?
MALE 5-9 year 10 0.025 .. ?
..
..
FEMALE 0-4 3 0.03 .... ?
FEMALE 5-9 12 0.025 .... ?
I know the algebra and can do this in Fortran but in Stata? I need it
for each record and the overall data.
Can anyone please suggest a solution, perhaps a program, that I can
enter Observed and Expected as parameters and derive a two-tailed
p-value for each record?
------------------------------------------------------------
You may use -ci- with the -poisson- option. Using your example from above (with very small expected numbers):
clear
input sex age obs exp
1 0 4 0.05
1 5 10 0.025
2 0 4 0.03
2 5 12 0.025
end
sort sex age
by sex age: ci obs , poisson exposure(exp)
---------------------------------------------------------------------------------------------------
-> sex = 1, age = 0
-- Poisson Exact --
Variable | Exposure Mean Std. Err. [95% Conf. Interval]
-------------+---------------------------------------------------------------
obs | .05 80 40 21.79731 204.8318
---------------------------------------------------------------------------------------------------
-> sex = 1, age = 5
-- Poisson Exact --
Variable | Exposure Mean Std. Err. [95% Conf. Interval]
-------------+---------------------------------------------------------------
obs | .025 400 126.4911 191.8155 735.6142
---------------------------------------------------------------------------------------------------
-> sex = 2, age = 0
-- Poisson Exact --
Variable | Exposure Mean Std. Err. [95% Conf. Interval]
-------------+---------------------------------------------------------------
obs | .03 133.3333 66.66667 36.32885 341.3863
---------------------------------------------------------------------------------------------------
-> sex = 2, age = 5
-- Poisson Exact --
Variable | Exposure Mean Std. Err. [95% Conf. Interval]
-------------+---------------------------------------------------------------
obs | .025 480 138.5641 248.023 838.4634
Hope this helps
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, work: +45 8942 6090
Phone, home: +45 8693 7796
Fax: +45 8613 1580
E-mail: [email protected]
_________________________________________________________
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