There exists 3 sets of numbers. I have the 99th percentile (p99) of each set and the cardinality of the set, but not the values in the set themselves.
- p99: 540, cardinality: 215
- p99: 288, cardinality: 4
- p99: 432, cardinality: 78
What is the most accurate way to estimate the combined p99 of those 3 sets without having access to the original data?
Right now I'm debating the follow 2 options:
- Simply use the p99 value of the set with the highest cardinality.
- Use a weighted average of the p99 values
Are there better, more accurate options?