Converts Weibull data (failure, suspension, and interval-censored times) into a format suitable for reliability growth analysis (RGA). The function handles exact failure times, right-censored suspensions, and interval-censored data. It approximates interval-censored failures by placing them at the midpoint of the interval. The output is a data frame with cumulative time and failure counts. This format can be used with RGA models such as Crow-AMSAA.
Arguments
- failures
A numeric vector of exact failure times. Each failure time indicates when an item failed during the observation period.
- suspensions
A numeric vector of suspension (right-censored) times. A suspension indicates that the item was removed from observation at that time without failure. This parameter is optional and can be NULL if there are no suspensions.
- interval_starts
A numeric vector of interval start times (lower bound of censoring). This parameter is optional and can be NULL if there are no interval-censored data. If provided, it must be the same length as
interval_ends.- interval_ends
A numeric vector of interval end times (upper bound of censoring). This parameter is optional and can be NULL if there are no interval-censored data. If provided, it must be the same length as
interval_starts.
Value
The data frame contains two columns:
- CumulativeTime
Cumulative time at each failure event.
- Failures
Number of failures at each cumulative time point.
The function approximates interval-censored failures by placing them at the midpoint of the interval.
Examples
failures <- c(100, 200, 200, 400)
suspensions <- c(250, 350, 450)
interval_starts <- c(150, 300)
interval_ends <- c(180, 320)
result <- weibull_to_rga(failures, suspensions, interval_starts, interval_ends)
print(result)
#> CumulativeTime Failures
#> 1 100 1
#> 2 265 1
#> 3 465 2
#> 6 1225 1
#> 8 1975 1