[R] quasi-Poisson regression in stats glm vs aod quasipois

[John P. Burkett]

For quasi-Poisson regression, I have tried to compare the output of the 
quasipois function in the aod package to the output of the glm function 
with family=quasi(link="log", variance="mu^2") in the stats package. 
The standard errors are about 32.5 times larger in the former than in 
the latter. If anyone can explain the difference, I would be most grateful.

I am running R version 2.6.1 and aod version 1.1-24 under Gentoo Linux.

In case they are of diagnostic value, I am attaching my R code 
(compare.R), my data set (visitsbymonth1990_2006.csv), and my output 
file (compare.Rout).

Best regards,
John

-- 
John P. Burkett
Department of Environmental and Natural Resource Economics
and Department of Economics
University of Rhode Island
Kingston, RI 02881-0808
USA

phone (401) 874-9195
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