Computing engine behind sclr
.
sclr_fit(y, x, tol = 10^(-7), n_iter = NULL, max_tol_it = 10^4)
A vector of observations.
A design matrix.
Tolerance. Used when n_iter
is NULL
.
Number of Newton-Raphson iterations. tol
is ignored when
this is not NULL
.
Maximum tolerated iterations. If it fails to converge within this number of iterations, will return with an error.
The likelihood maximisation uses the Newton-Raphson algorithm. Initial values are always 1 for the covariate coefficients (and the associated intercept) and the proportion of infected for the baseline risk. The algorithm will pick a new guess and restart under a set of conditions. 1) Algorithm's iteration produces estimate guesses that cannot be used - baseline risk outside of (0, 1) (likelihood undefined). 2) The second derivative matrix produced by the current estimates is "bad" - positive diagonal or missing values due to failing large number calculations