Experiment ID
85
Pathogen
Agent Strain
ATCC 6605
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
guinea pig
# of Doses
6.00
Dose Units
spores
Μodel
exponential
k
7.11E-06
LD50/ID50
9.75E+04
Description
Guinea pig/ATCC 6605 Strain model data 
Dose Dead Survived Total
30 0 6 6
300 1 5 6
3000 0 10 10
3E+04 3 7 10
3E+05 8 2 10
3E+06 10 0 10

 

Goodness of fit and model selection
Model Deviance Δ Degrees 
of freedom
χ20.95,1 
p-value
χ20.95,m-k 
p-value
Exponential 8.56 1.81 5 3.84 
0.178
11.1 
0.128
Beta Poisson 6.75 4 9.49 
0.15
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 7.11E-06 2.60E-06 3.52E-06 3.87E-06 1.61E-05 1.97E-05 2.85E-05
ID50/LD50/ETC* 9.75E+04 2.43E+04 3.52E+04 4.30E+04 1.79E+05 1.97E+05 2.66E+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