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Total (Tot)
For time or cost statistics, the total is the sum of time or costs accumulated by the transactions that have completed for each activity. For count statistics, the total is the number of transactions that have been counted at each activity. If you apply a filter to the statistic, then only specific completed transactions are counted.
Average (Avg or Tavg)
For time or cost statistics, the average (Avg) is the total time or costs divided by the number of completed transactions for each activity. For count statistics, the two types of average are Avg and Tavg.
Avg is the observation-based average. This is the sum of the value of the statistic, when observed, divided by the number of observations taken.
Tavg is the time-weighted average. This is the average after weighting each count based on the amount of time that the observed count occurred.
For example, consider a simulation model where one transaction waits for an hour, and another transaction arrives after that hour and waits for 15 minutes before both transactions are processed at the elapsed 1.25 hours. The average (Avg) wait count is 1 observed waiting, plus 2 observed waiting, divided by the 2 observations, for an average of 1.5. Written as an equation, this is (1 + 2)/2 = 1.5. When we consider the time-weighted average (Tavg) wait count, we have 1 waiting for 1.25 hours, plus 1 waiting for 0.25 hours, divided by the total time of 1.25 hours, for an average of 1.2. Written as an equation, this is (1.25 + 0.25)/1.25 = 1.2.
For the count statistics average, iGrafx recommends that you use the time-weighted average (Tavg) when it is available.
Standard Deviation (Stdev or TStdev)
The magnitude of the statistic deviation from the average.
Maximum (Max)
The highest number accumulated for the statistic at any one point in time (the “high-water mark”).
Minimum (Min)
The lowest number accumulated for the statistic at any one point in time.
Final Value (Final)
The value of the statistic at report time (when simulation ends).
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