Provides functions for the analysis of
occupational and environmental data with non-detects. Maximum
likelihood (ML) methods for censored log-normal data and
non-parametric methods based on the product limit estimate (PLE)
for left censored data are used to calculate all of the
statistics recommended by the American Industrial Hygiene
Association (AIHA) for the complete data case. Functions for
the analysis of complete samples using exact methods are also
provided for the lognormal model. Revised from 2007-11-05
'survfit~1'.