mice/ scrapie strain C506M3 model data [1]
| Dose |
Dead |
Survived |
Total |
| 125 |
0 |
11 |
11 |
| 1250 |
1 |
9 |
10 |
| 12500 |
2 |
8 |
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 |
1.34 |
0.99 |
2 |
3.84
0.32 |
5.99
0.512 |
| Beta Poisson |
0.35 |
1 |
3.84
0.554 |
| 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 |
2.4E-05 |
1.00E-13 |
1.00E-13 |
7.23E-06 |
5.47E-05 |
5.81E-05 |
7.44E-05 |
| ID50/LD50/ETC* |
2.89E+04 |
9.32E+03 |
1.19E+04 |
1.27E+04 |
9.58E+04 |
6.92E+12 |
6.92E+12 |
| *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
QMRA