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Experiment ID
223
Pathogen
Shigella flexneri
Contains Preferred Model
0
Reference
Inoculum Size in Shigellosis and Implications for Expected Mode of Transmission
Host type
human
# of Doses
4.00
Μodel
beta-Poisson
a
1.35E-01
N50
3.11E+03
LD50/ID50
3.11E+03
Dose Units
CFU
Response
illness
Agent Strain
2a (strain 2457T)
Exposure Route
oral (in milk)
Experiment Dataset
Description: 
Model data for Shigella flexneri (2a, strain 2457T) in the human [1]
Dose Illness Not illness Total
180 9 27 36
5000 28 21 49
1E+04 52 36 88
1E+05 14 10 24

 

Goodness of fit and model selection
Model Deviance Δ Degrees 
of freedom		 χ20.95,1 
p-value		 χ20.95,m-k 
p-value
Exponential 154 153 3 3.84 
0		 7.81 
0
Beta Poisson 1.69 2 5.99 
0.429
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 1.35E-01 9.86E-04 1.22E-02 6.85E-02 2.06E-01 2.22E-01 2.58E-01
N50 3.11E+03 5.09E+01 4.31E+02 9.64E+02 7.49E+03 9.14E+03 1.89E+04

 

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