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Experiment ID
84
Pathogen
Bacillus anthracis
Contains Preferred Model
0
Reference
Postexposure Prophylaxis against Anthrax: Evaluation of Various Treatment Regimens in Intranasally Infected Guinea Pigs
Host type
guinea pig
# of Doses
6.00
Μodel
beta-Poisson
a
5.49E-01
N50
2.85E+04
LD50/ID50
2.85E+04
Dose Units
spores
Response
death
Agent Strain
Vollum
Exposure Route
inhalation
Experiment Dataset
Description: 
Guinea pig/Vollum Strain model data [1]
Dose Dead Survived Total
200 0 4 4
2000 0 8 8
2E+04 6 6 12
2E+05 10 2 12
2E+06 7 1 8
2E+07 7 0 7

 

Goodness of fit and model selection
Model Deviance Δ Degrees 
of freedom		 χ20.95,1 
p-value		 χ20.95,m-k 
p-value
Exponential 29.2 26.6 5 3.84 
2.46e-07		 11.1 
2.11e-05
Beta Poisson 2.58 4 9.49 
0.631
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 5.49E-01 2.55E-01 3.03E-01 3.32E-01 5.51E+00 2.45E+03 6.16E+03
N50 2.85E+04 1.00E+04 1.25E+04 1.43E+04 6.57E+04 7.85E+04 1.09E+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

References

  1. Altboum, Z., Gozes Y., Barnea A., Pass A., White M., & Kobiler D. (2002).  Postexposure prophylaxis against anthrax: evaluation of various treatment regimens in intranasally infected guinea pigs. Infection and immunity. 70, 6231–6241.