The spduration package provides functions to estimate split-population duration regression models in which only a subset of the population is at risk for failure, while the remainder is immune, or cured, from the possibility of experiencing a failure event. In practice, this class of models also may produce better performance in sparse data with few actual failure events.

The main function `spdur`

is used to estimate the model
objects with class `spdur`

.

Postestimation tools include `predict.spdur`

, for calculating
fitted values with arbitrary data and for several probabilities that
might be of interest, as well as `plot.spdur`

for visual
display of model fit.

Boag, J.W. 1949. ``Maximum Likelihood Estimates of the Proportion of Patients Cured by Cancer Therapy.'' <http://www.jstor.org/stable/2983694>

Berkson, J. and Gage, R.P. ``Survival Curve for Cancer Patients Following Treatment.'' <http://www.jstor.org/stable/2281318>

Leisch, Friedrich. 2009. ``Creating R Packages: A Tutorial.''

Schmidt, Peter and Witte, Ann Dryden. 1989. ``Predicting Criminal Recidivism Using "Split Population" Survival Time Models.'' <doi:10.1016/0304-4076(89)90034-1>

Svolik, Milan. 2008. ``Authoritarian Reversals and Democratic Consolidation.'' American Political Science Review.