Percentile function doesn't calculate right?

Questions & Answers
,
1

Hello,

I’m trying to measure “85 Percentile” of cycle time for issues.
I’m using following Measure:

Percentile(
  Filter(
    Descendants([Issue].CurrentMember,[Issue].[Issue]),
    -- first transition to the category "Done" in the current Time dimension period
    DateInPeriod(
      (
        [Measures].[Transition to status first date],
        [Transition Status.Category].[Done],
        [Time].CurrentHierarchy.DefaultMember
      ),
      [Time].CurrentHierarchyMember
    )
    AND
    -- has a transition out of category "In Progress"    
    ([Measures].[Transitions from status],
    [Transition Status.Category].[In Progress],
    [Time].CurrentHierarchy.DefaultMember) > 0
  ),
  -- number of days spent in category "In Progress"
  ([Measures].[Days in transition status],
  [Transition Status.Category].[In Progress],
  [Time].CurrentHierarchy.DefaultMember),
  -- 85 percentile
  85
)

I expect to get Cycle Time for 85% of tasks, but getting 85% of maximum Cycle Time value.

EaziBi Percentile
EaziBi Percentile1249×596 7.26 KB

2

Hi @danil.chernyshev

Welcome to the eazyBi community!

Your Percentile calculation seems correct and does exactly what you are looking for: it orders all filtered issues by their cycle time, takes 85% of issues (starting from those with the lowest value), and shows the value for the issue around that 85th % limit (in your drawing, the green line).

There is an example report where I used your formula as a base to compare what value would be 85% from the max cycle time value:

  1. “Percentile 85% cycle times” is your formula (green line in your drawing)
  2. I calculated the maximal cycle time value for the same issue set/time period (“Max cycle time value” - use the same set and numerical expression for Max() calculation))
  3. and then I calculated 85% from that maximal cycle time value (red line in your drawing). For “85% of max cycle time value” multiplied the calculated max value by 0.85.

image
image1610×984 108 KB

Also, starting from eazyBI 6.5. version, there are build in cycle time calculations, you may try and define your cycles using them: Issue cycles

You may expand one time period to the issue level, display issue cycle times and then find 85% percentile manually and compare it with the calculated one and share the result; probably, I missed something in your question. If it is more convenient to share more data privately, we may continue via support email.

Best,
Ilze, support@eazybi.com