Package: fuzzySurvival 0.1.0

fuzzySurvival: Fuzzy Survival Analysis with Vague Event Times and Fuzzy Censoring

Fuzzy survival analysis for data in which event times and/or failure indicators are vague, for instance when a failure is only known to have occurred during the second quarter of a year, or when it is uncertain whether a subject lost to follow-up had in fact failed. Vague information is represented by fuzzy numbers. The package provides a fuzzy product-limit estimator obtained from nested alpha-cuts of the fuzzy survival function, a fuzzy Cox proportional hazards model with fuzzy coefficient and hazard ratio estimates, and a fuzzy log-rank test. Type-reduction utilities for summarizing fuzzy estimates by single numbers, a simulation engine for validation studies, plotting, print and summary methods, and alpha-cut based confidence bands are provided. The bounds are computed at the alpha-cuts of the fuzzy event times, so the alpha-cut intervals returned for the survival function, the regression coefficients and the test statistic are nested by construction.

Authors:Mukul Bijalwan [aut, cre], Gunjan Aggrwal [aut], Mukul Jain [aut]