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
Computer Files
◦ Database
◦ Spreadsheets
◦ Raw Data
Video Records
 Hard Copy Files
& Documents
 Interviews
Video
 Observation of
running system
 Interviews


Existing
Observation
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To help design
model
 Interviews
 Observation
 Minimum
necessary
To obtain input
parameters
 Adequate
amount for
statistical tests


Preliminary
Detailed
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
Data to Determine
◦ Layout of system
◦ Entities of
importance
◦ Flow of entities
◦ Problems


Data for
◦ Arrivals
◦ Services
◦ Queues
◦ Anomalies
Rough estimates of
times
Preliminary
Detailed
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Focus on data related to problems &
objectives
 Enough data for statistical significance
 Continuous data

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Depends on Simulation Objectives &
Level of Activity
 Days of week
◦ Busiest, Typical, Slowest
◦ All, Certain ones

Time of day

Length of time
◦ Busiest, Typical, Slowest
◦ Start-up, Wind-down
◦ Adequate numbers
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
Minimum of 2 collectors for each
major entity
◦ One watches & times; One records

Factors
◦ Level of Activity
◦ Proximity of areas to be observed
◦ Visibility
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Collectors can have NO Effect on the
system!
Should be located “outside” the
system
 Cannot utilize any resource
 Never interfere
 Best if not seen

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
Collect information necessary to
reproduce system activity
◦ NOTE: That is not everything!!

Example: Single Queue & Server System

Time Units
◦ Arrival Time, Begin Service, End Service
◦ Allows calculation of all remaining values
of interest. How?
◦ Smallest necessary (seconds, minutes…)
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Arriva l Time
Hr:Min:Sec
Begin Service
End Service
1
0:0:0
0:0:0
0:5:26
2
0:3:30
0:5:26
0:10:45
3
0:12:0
0:12:0
0:15:50
4
0:13:24
0:15:50
0:19:55
Customer
Number
Comments??
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
A description of process that includes
◦ Method(s) for collection
◦ Timeline for data collection process &
completion
◦ List of data items to be collected
◦ Number of collectors
◦ Dates & times of actual data collected (if not
observed in real-time)
◦ Justification for each of the above
◦ Diagrams as necessary
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
A description of completed collection
process that includes
◦ Restatement of “Plan” & any changes to
original plan
◦ Results of Statistical Analysis of data
◦
◦
◦
◦
 Graphs, Averages, Max, Min
Summary of results
Relation of results to clients objectives
Recommendations
Diagrams as necessary
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Select System
 Design & Write Data Collection Plan
 Observe & Collect
 Complete Data Analysis
 Write Data Collection Report

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