Human/Salmonella newportmodel data [1]]
Dose |
Infected |
Non-infected |
Total |
152000 |
3 |
3 |
6 |
385000 |
6 |
2 |
8 |
1350000 |
6 |
0 |
6 |
|
Goodness of fit and model selection
Model |
Deviance |
Δ |
Degrees
of freedom |
χ20.95,1
p-value |
χ20.95,m-k
p-value |
Exponential |
0.16 |
-3.32e-05 |
2 |
3.84
1 |
5.99
0.923 |
Beta Poisson |
0.16 |
1 |
3.84
0.689 |
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 |
3.97E-06 |
1.75E-06 |
2.16E-06 |
2.32E-06 |
7.36E-06 |
9.04E-06 |
1.27E-05 |
ID50/LD50/ETC* |
1.74E+05 |
5.45E+04 |
7.67E+04 |
9.41E+04 |
2.98E+05 |
3.20E+05 |
3.97E+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