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Experiment ID
248
Pathogen
Salmonella nontyphoid
Agent Strain
strain 533
Contains Preferred Model
No
Reference
Hornick, R. B., Music, S. I., Wenzel, R. ., Cash, R. ., Libonati, J. P., Snyder, M. J., & Woodward, T. E. (1971). The Broad Street pump revisited: response of volunteers to ingested cholera vibrios. Bulletin of the New York Academy of Medicine, 47, 10. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1749960/
Exposure Route
intraperitoneal
Response
death
Host type
mice
# of Doses
7.00
Dose Units
CFU
Μodel
beta-Poisson
a
1.08E-01
N50
9.66E+06
LD50/ID50
9.66E+06
Description
Mice/ Salmonella strain 533 data 
Dose Dead Survived Total
1E+04 20 180 200
1E+05 17 153 170
1E+06 11 29 40
3160000 6 24 30
1E+07 12 8 20
3.16E+07 17 3 20
1E+08 19 1 20

 

Goodness of fit and model selection
Model Deviance Δ Degrees 
of freedom		 χ20.95,1 
p-value 		χ20.95,m-k 
p-value
Exponential 214 165 6 3.84 
0 		12.6 
0
Beta Poisson 48.7 5 11.1 
2.56e-09
Neither the exponential nor beta-Poisson fits well; beta-Poisson is less bad.

 

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 1.08E-01 6.19E-02 7.06E-02 7.52E-02 1.79E-01 1.98E-01 2.44E-01
N50 9.66E+06 1.93E+06 2.43E+06 2.82E+06 5.38E+07 8.11E+07 2.13E+08

 

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

  • Meynell, G. G., & Meynell, E. W. (1958). The growth of micro-organisms in vivo with particular reference to the relation between dose and latent period. The Journal of Hygiene, 56(3). https://doi.org/10.1017/s0022172400037827