[R] 'geepack' and 'gee' package outputs

[cmc]

Hi, having used both the gee pacakge and the geepack package, i am unsure of
how to interpret the results.

Here are the results from the geeglm function from the geepack package

> gee2<-geeglm(data$erythema~data$product, data = data, id=subject,
> family=binomial, corstr="independence")
Warning message:
In model.response(mf, "numeric") :
  using type="numeric" with a factor response will be ignored
> summary(gee2)

Call:
geeglm(formula = data$erythema ~ data$product, family = binomial, 
    data = data, id = subject, corstr = "independence")

 Coefficients:
                Estimate   Std.err Wald Pr(>|W|)    
(Intercept)     3.14e+16  5.05e+14 3864   <2e-16 ***
data$product2   3.69e+16  8.12e+14 2062   <2e-16 ***
data$product3  -2.67e+16  4.67e+14 3267   <2e-16 ***
data$product4  -2.59e+16  5.04e+14 2642   <2e-16 ***
data$product5  -1.41e+16  5.30e+14  710   <2e-16 ***
data$product6  -2.59e+16  4.96e+14 2722   <2e-16 ***
data$product7   1.55e+17  2.07e+15 5646   <2e-16 ***
data$product8   2.90e+16  7.87e+14 1362   <2e-16 ***
data$product9  -2.43e+16  4.79e+14 2584   <2e-16 ***
data$product10 -2.04e+16  5.05e+14 1632   <2e-16 ***
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 

Estimated Scale Parameters:
            Estimate  Std.err
(Intercept) 5.51e+15 5.58e+38

Correlation: Structure = independenceNumber of clusters:   33   Maximum
cluster size: 40 
>


And here are the results for the gee function from the gee package

> gee(data$erythema~data$product, data = data, id=subject, family=binomial,
> corstr="independence")
Beginning Cgee S-function, @(#) geeformula.q 4.13 98/01/27
running glm to get initial regression estimate
   (Intercept)  data$product2  data$product3  data$product4  data$product5 
data$product6 
        -1.181          0.488         -1.863         -1.863         -0.800        
-1.701 
 data$product7  data$product8  data$product9 data$product10 
         1.456          0.782         -1.863         -1.121 
Error in gee(data$erythema ~ data$product, data = data, id = subject,  : 
  Cgee: error: logistic model for probability has fitted value very close to
1.
estimates diverging; iteration terminated.
> 


I know from doing multinomial logit regression that product 7 greatly
increases levels of erythema, and products 2 and 8 have a slight increase in
erythema. However, i am unsure how to read the above results and be able to
present them to other people.

Any help much appreciated. 


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