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Experiment ID
86
Pathogen
Bacillus anthracis
Contains Preferred Model
0
Reference
Studies on respiratory infection
Host type
monkey
# of Doses
9.00
Μodel
exponential
k
7.16E-06
LD50/ID50
9.69E+04
Dose Units
spores
Response
death
Agent Strain
Vollum
Exposure Route
inhalation
Experiment Dataset
Description: 
Rhesus Macaques/Vollum Strain model data [1]
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

  1. Druett, HA., Henderson DW., Packman L., & Peacock S. (1953).  Studies on respiratory infection: I. The influence of particle size on respiratory infection with anthrax spores. Epidemiology & Infection. 51, 359–371.