Valve Seats Dataset


Valve seats wear out in certain diesel engines, each with 16 valve seats. The dataset served as an example of recurrence data in Nelson (1995), which consists of valve-seat replacements on 41 engines in a fleet. The covariates are named ID, Days, and No., where

  • ID: The engine number;

  • Days: Engine age in days;

  • No.: Event indicator, '1' for a valve-seat replacement and, '0' for the censoring age of an engine.


A data frame with 89 rows and 3 variables.


Nelson, W. (1995), Confidence Limits for Recurrence Data-Applied to Cost or Number of Product Repairs, Technometrics, 37, 147–157.

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