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TL
June 15th, 2005, 08:06 AM
Hi
I have a question related to the three types of censored data described in the Life Data Analysis Reference, http://www.weibull.com/LifeDataWeb/data_classification.htm.

Three types of censored data is described. However, if I have the following data set, which might be mileages when a specific car component has been repaired at a workshop. I have 4 cars, all with different mileages at the time of the datacollection.

1000 km No failure
800 km Failure
200 km No failure
500 km Failure

I wonder what type of data I have. I know the exact mileages of the failures and no failures so it is neither left or interval censored. But is it right censored data? As I understand all censored times must be equal when it is right censored data, which they are not in my case due to the different current mileages.

tarik
June 15th, 2005, 10:40 AM
Your data is mixed, you have 2 exact failures at 800 and 500 and 2 right censored (suspended) data at 1000 and 200. You don't have interval data, unless you are not sure when the 2 failures occurred (for you example you think that the 1st failure that occurred at 800 in fact happened sometime between 700 and 900). Unlike what you said, right censored (suspended) times don't have to be equal.