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Arlington Police DepartmentCrime Management

Ron AndrewsBlake Robinson

Advisors: Bill Edmonds, Jim Mallard & Chief Bowman

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Perplexing the mind?• Where would crime incidences only occur during the day (up till 10:00pm) ?

and• At a rate of four times the surrounding areas?

and• Mostly affect motor vehicles?

– Hint: Data Analysis Intuition & cell 206

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Agenda• Executive Summary

– Nature of Project

• APD Overview– Primary Goals

• Current Operations• Geographical Information System• Cell & Grid Development• Statistical & Data Analysis

– Incident Concentration

• Model Development– Assignment Network (Pure Network)

• Recommendations & Results

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Executive Summary• Management of Crime• Goal: Reduction of Crime Incidents by

25% over the next 3 years• Insight into class one crimes (burglary,

theft, murder, homicides and rape) and raw data

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APD Overview

• Crime Triangle• Over 300,000 incidents per year– Approx: 40,000 crime related (≈13%)

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Current Operations• 4 Police Districts– North, South, East, West– Police Station

• How police incidences are recorded • Incidences are assigned priorities • Insight into crime by location limited

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Geographical Information System• G.I.S is a system that captures, stores, analyzes, manages

and presents data with reference to geographic location• Provides detailed information which is mapable • How do you effective redraw each district boundary line

to effectively serve each area?

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Grid & Cell Development• Total Cells: 472 • ½ Mile cell structure • 1000 feet cell Structure• Euclidean distance at centroid

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ArcGIS

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Current Boundary

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Statistical & Data Analysis• Bar Chart• Scatter Chart• Arlington total cell statistics• Outlier Cell 206• Incident Concentration

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1 17 33 49 65 81 97 1131291451611771932092252412572732893053213373533693854014174334494650

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120

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Bar Chart: Incident Totals

Series1

Cell Number

Incid

ents

Per

Cel

l

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0 50 100 150 200 250 300 350 400 450 5000

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80

100

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Scatter Plot: Incident Totals

Series1

Cell Number

Num

ber o

f Inc

iden

ts

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Combined Cells 1-472

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Cell 206

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Incident ConcentrationCells: 181, 180, 179, 207, 206, 205, 234, 233, 232, 263, 262, & 261

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Incident ConcentrationCells: 181, 180, 179, 207, 206, 205, 234, 233, 232, 263, 262, & 261

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Model Development• District Boundaries• Constraints (can be ambiguous)– Distance– Time– Volume– Political – Operational

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Model Development Cont.• Assignment Network (Pure Network)• 1888 Variables• 476 Constraints• 1 Objective Function

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Model File

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Data File

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Output File

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District Boundary Changes

24*New Boundaries not placed accordingly to scale*

New Boundary

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Recommendations & Results• Plans to help reduce crime incidents in target location:– Immediate Impact

• Police towers• Higher Police presence• Reminding safety cards on vehicle windshields

– Long Term• Centralized and monitored entrance to mall• Parking Garage vs Parking Lot

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Recommendations & Results Cont.• Plans for utilization of assignment network

model:–Minor changes in district boundaries

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Questions