- a
The parameter a of the Denny model, l(t)=1/(1+a*(t/(105-t))^3+b*sqrt(exp(t/(105-t))-1)+c*(1-exp(-2*t))).
- b
The parameter b of the Denny model, l(t)=1/(1+a*(t/(105-t))^3+b*sqrt(exp(t/(105-t))-1)+c*(1-exp(-2*t))).
- c
The parameter c of the Denny model, l(t)=1/(1+a*(t/(105-t))^3+b*sqrt(exp(t/(105-t))-1)+c*(1-exp(-2*t))).
- t
Age (vector OK) in years. The t must be less than 105, otherwise the value by Denny() become 0.
- initialpar
Initial value for the parameters to be estimated. If not given, rep(0.1, 3) is used.
- data
Actual vector of qx in the lifetable to be used to obtain the best-fit parameters of the Denny's model. If the ages for qx are equal or elder than 105 years old, those will be ignored in fitting.
- mode
Which of lifetable functions should be used to calculate the RMSE: 1 qx, 2 dx, otherwise lx. Default is 3.
- Method
The method to be used in optim() function. Default is "Nelder-Mead".
- ...
Other options to be passed to optim().