You can structure each column so that it contains individual observations (one row = one observation) or unique observations with a corresponding column of frequencies (counts).
Here are the same data structured both ways:
Individual observations |
Frequency columns | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Frequency columns are useful for data where you have large numbers of observations with common failure and censoring times. For example, warranty data usually includes large numbers of observations with common censoring times.