Data Collectionfor Simulation
Sources of Data
Computer FilesDatabaseSpreadsheetsRaw DataVideo RecordsHard Copy Files & DocumentsInterviews
VideoObservation of running systemInterviews
When & How Much to Collect?
To help design modelInterviewsObservationMinimum necessary
To obtain input parametersAdequate amount for statistical tests
What to collect?
Data to DetermineLayout of systemEntities of importanceFlow of entitiesProblemsRough estimates of times
Focus on data related to problems & objectivesEnough data for statistical significanceContinuous data
What to collect? More…
Depends on Simulation Objectives & Level of ActivityDays of weekBusiest, Typical, SlowestAll, Certain onesTime of dayBusiest, Typical, SlowestStart-up, Wind-downLength of timeAdequate numbers
Minimum of 2 collectors for each major entityOne watches & times; One recordsFactorsLevel of ActivityProximity of areas to be observedVisibility
How Many Collectors?
Collectors can have NO Effect on the system!Should be located “outside” the systemCannot utilize any resourceNever interfereBest if not seen
Collect information necessary to reproduce system activityNOTE: That is not everything!!Example: Single Queue & Server SystemArrival Time, Begin Service, End ServiceAllows calculation of all remaining values of interest. How?Time UnitsSmallest necessary (seconds, minutes…)
Sample Collection FormSingle Queue-Single Server
A description of process that includesMethod(s) for collectionTimeline for data collection process & completionList of data items to be collectedNumber of collectorsDates & times of actual data collected (if not observed in real-time)Justification for each of the aboveDiagrams as necessary
Data Collection Plan
A description of completed collection process that includesRestatement of “Plan” & any changes to original planResults of Statistical Analysis of dataGraphs, Averages, Max, MinSummary of resultsRelation of results to clients objectivesRecommendationsDiagrams as necessary
Data Collection Report
Select SystemDesign & Write Data Collection PlanObserve & CollectComplete Data AnalysisWrite Data Collection Report
Data Collection Assignment