Experiment ID
232, 233
Pathogen
Agent Strain
strain I
Contains Preferred Model
Yes
Reference
McCullough, N. ., & Elsele, C. . (1951). Experimental Human Salmonellosis: I. Pathogenicity of Strains of Salmonella Meleagridis and Salmonella Anatum Obtained from Spray-Dried Whole Egg. Oxford Journal of Infectious Diseases, 88(3). https://doi.org/https://doi.org/10.1093/infdis/88.3.278
Exposure Route
oral (with eggnog)
Response
positive stool culture
Host type
human
# of Doses
16.00
Dose Units
CFU
Μodel
beta-Poisson
a
3.18E-01
N50
3.71E+04
LD50/ID50
3.71E+04
Description
Human/ Salmonella anatum strain I & II pooled data [4]
Dose Positive stool culture No positive stool culture Total
12000 2 3 5
24000 3 3 6
66000 4 2 6
89000 5 1 6
93000 1 5 6
141000 3 3 6
256000 5 1 6
448000 4 2 6
587000 4 2 6
860000 6 0 6
1040000 6 0 6
3.9E+06 4 2 6
1E+07 6 0 6
2.39E+07 5 1 6
4.45E+07 6 0 6
6.73E+07 8 0 8

 

Goodness of fit and model selection
Model Deviance Δ Degrees 
of freedom
χ20.95,1 
p-value
χ20.95,m-k 
p-value
Exponential 138 119 15 3.84 
0
25 
0
Beta Poisson 18.9 14 23.7 
0.168
Beta-Poisson fits better than exponential; cannot reject good fit for beta-Poisson.

 

Optimized parameters for the beta-Poisson model, from 10000 bootstrap iterations
Parameter MLE estimate Percentiles
0.5% 2.5% 5% 95% 97.5% 99.5%
α 3.18E-01 1.35E-01 1.71E-01 1.92E-01 5.70E-01 6.66E-01 9.56E-01
N50 3.71E+04 1.40E+03 5.50E+03 8.86E+03 8.82E+04 1.00E+05 1.30E+05

 

Parameter scatter plot for beta Poisson model ellipses signify the 0.9, 0.95 and 0.99 confidence of the parameters.

beta Poisson model plot, with confidence bounds around optimized model