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>but I was specificly interested in calculating QAIC and QAICc from
>a glm fitted with the "family=quasibinomial" option.

If you use "family=quasibinomial(link = "logit")" in glm(),
the program will be:

function ()
{
   xx <- c(1,2,3,4,5,6,7,8,9,10)
   yy <- c(1,0,1,0,0,1,0,1,1,1)
   data1 <- data.frame(x=xx, y=yy)
   out1 <- glm(y~x, data=data1, family=quasibinomial(link = "logit"))
   print(out1)
   aic0 <- out1$aic
   print("aic0")
   print(aic0)

   dev1 <- out1$deviance
   aic1 <-  dev1+ 2*2
   print("aic1")
   print(aic1)

   c1 <- 2.5
   qaic1 <-  dev1/c1+ 2*2
   print("qaic1")
   print(qaic1)
}

The result is:
Call:  glm(formula = y ~ x, family = quasibinomial(link = "logit"),
data = data1)

Coefficients:
(Intercept)            x
    -0.7300       0.2131

Degrees of Freedom: 9 Total (i.e. Null);  8 Residual
Null Deviance:      13.46
Residual Deviance: 12.63        AIC: NA
[1] "aic0"
[1] NA
[1] "aic1"
[1] 16.63054
[1] "qaic1"
[1] 9.052216

   As you pointed out, glm() does not output the value of either AIC or
QAIC.
You are supposed to calculate those values. I guess that it is because AIC
is not
appropriate for this case, and the concept of QAIC has not been authorized
yet.

K. Takezawa

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