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Experiment ID
252
Pathogen
Prion
Agent Strain
BSE agent
Contains Preferred Model
No
Reference
John, D. T., & Hoppe, K. L. (1990). Susceptibility of Wild Mammals to Infection with Naegleria fowleri. The Journal of Parasitology, 76, 6.
Exposure Route
unknown type of injection
Response
infection
Host type
mice
# of Doses
4.00
Dose Units
ID50 unit
Μodel
exponential
k
6.93E-01
LD50/ID50
1
Description
mice/BSE agent model data 
Dose Infected Non-infected Total
0.0186 0 13 13
0.186 4 12 16
1.86 9 5 14
18.6 13 0 13

 

Goodness of fit and model selection
Model Deviance Δ Degrees 
of freedom		 χ20.95,1 
p-value 		χ20.95,m-k 
p-value
Exponential 2.78 0.763 3 3.84 
0.382 		7.81 
0.427
Beta Poisson 2.01 2 5.99 
0.365
Exponential is preferred to beta-Poisson; cannot reject good fit for exponential.

 

Optimized k parameter for the exponential model, from 10000 bootstrap iterations
Parameter MLE estimate Percentiles
0.5% 2.5% 5% 95% 97.5% 99.5%
k 6.93E-01 3.03E-01 3.69E-01 4.16E-01 1.14E+00 1.32E+00 1.70E+00
ID50/LD50/ETC* 1E+00 4.08E-01 5.27E-01 6.08E-01 1.67E+00 1.88E+00 2.29E+00
*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

  • Taylor, D. M., Woodgate, S. L., & Atkinson, M. J. (1995). Inactivation of the bovine spongiform encephalopathy agent by rendering procedures. Veterinary Record, 137(24). Retrieved from https://pubmed.ncbi.nlm.nih.gov/8746849/