[R] System Reliability Metrics

[Jon Stearley]

On Dec 21, 2005, at 11:02 AM, Jon Stearley wrote:

> I need to calculate some metrics such as Mean Time Between Failure  
> (MTBF), etc (see http://www.cs.sandia.gov/~jrstear/ras for a more  
> complete list).  I have observations like
>
>                  start                 end                state
>  1 2005-11-11 09:05:00 2005-11-11 12:20:00   Scheduled Downtime
>  2 2005-11-12 13:42:00 2005-11-12 14:45:00 Unscheduled Downtime
>
> where each row describes the system state between start and end  
> times.  Time between observations indicates a Production state.   
> The metrics of interest involve simple ratios of total time spent  
> in various states, number of transitions, etc.  I'd like to plot  
> period MTBF values (eg monthly vertical bars), as well as a  
> cumulative MTBF (eg a line whose last value indicates MTBF for the  
> entire time range), etc.
>
> What is the best approach in R towards these results?

I have found that the zoo package fills most of my needs.  Thanks.

-jon