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Experiment ID
86
Pathogen
Bacillus anthracis
Agent Strain
Vollum
Contains Preferred Model
No
Reference
Druett, H. A., Henderson, D. W., Packman, L. ., & Peacock, S. . (1953). Studies on respiratory infection. The Journal of Hygiene, 51, 3.
Exposure Route
inhalation
Response
death
Host type
monkey
# of Doses
9.00
Dose Units
spores
Μodel
exponential
k
7.16E-06
LD50/ID50
9.69E+04
Description
Rhesus Macaques/Vollum Strain model data
Dose Dead Survived Total
70300 1 7 8
77000 4 4 8
109000 5 3 8
138000 6 2 8
156000 5 3 8
161000 3 5 8
240000 8 0 8
3E+05 7 1 8
398000 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 11.3 -0.000503 8 3.84 
1 		15.5 
0.188
Beta Poisson 11.3 7 14.1 
0.128
Exponential is preferred to beta-Poisson; cannot reject good fit for exponential.

 

Optimized parameters for the exponential model, from 10000 bootstrap iterations
Parameter MLE estimate Percentiles
0.5% 2.5% 5% 95% 97.5% 99.5%
k 7.16E-06 4.99E-06 5.47E-06 5.71E-06 9.09E-06 9.51E-06 1.05E-05
ID50/LD50/ETC* 9.69E+04 6.63E+04 7.29E+04 7.63E+04 1.21E+05 1.27E+05 1.39E+05
*Not a parameter of the exponential model; however, it facilitates comparison with other models.

Parameter histogram for exponential model (uncertainty of the parameter)

 

Exponential model plot, with confidence bounds around optimized model

 

References