Go back to Flu Mortality
Result 1989-1990 epidemic 2 SIR model Baseline Different Alpha BFGS Jul (poi/neg fast C code)
For the guess of parameters beta1 = 0.3 alpha1 = 0.2 Ne = 3876.95 I1 = 1 beta2 = 0.3 alpha2 = 0.2 I2 = 1, we obtained
beta1 = 1.327932e+01 alpha1 = 1.246641e+01 Ne = 7.057050e+03 I1 = 2.074622e-01 beta2 = 2.619515e+01 alpha2 = 2.556590e+01 I2 = 1.609588e-03
So, this implies that f = 7.057050e+03/27653146 = 0.0002551988
The MLE was -72.4
The confidence intervals for the coefficients
2.5 % 97.5 %
beta1 1.324336e+01 1.370421e+01
alpha1 1.228706e+01 1.250254e+01
N 5.724233e+03 7.653800e+03
I1 1.444811e-01 1.335400e+00
beta2 2.544692e+01 2.629119e+01
alpha2 2.546842e+01 2.590520e+01
I2 2.380988e-03 8.542142e-03
It switched to a Poisson distribution when r > 1,000,000.
AICc value 168.9754
Weston: This AICc value is lower than the result for Jul 16th, 168.9891, which implies it had a better fit. I believe extending the range for r (up to 1,000,000 being neg bin before the switch) caused this slightly better fit.
Here’s a plot of the model with the data (black is the data, blue is the sum of the two models and baseline, red is the first SIR model, yellow is the second SIR model, and orange is the baseline)
Here are the two SIR models, overall data, and regional data (blue is the BC data, green is the Ontario data, and purple is the Quebec data).