2000 Systems Engineering Capstone Conference • University of Virginia
THE DESIGN AND IMPLEMENTATION OF REGIONAL CRIME ANALYSIS
PROGRAM: SMALL DEPARTMENT EDITION (ReCAP SDE)
Student Team: Grace Curry, Matt D’Acunto, Garland Lynn, Mark Sameit
Faculty Advisor: Dr. Donald Brown, Department of Systems Engineering
VIJIS Staff Advisor: Jason Dalton
Client Advisors: Lieutenant J.W. Gibson and Tom McKean
Charlottesville Police Department
Mike Schnurr
Albemarle Police Department
Butch Johnstone
Virginia Department of Criminal Justice Services
Nancy Lavigne
National Institute of Justice
KEYWORDS: Crime Analysis, Data Analysis, Law
Enforcement Information System, Geographical
Information System (GIS), Mapping
ABSTRACT
Police rely on judgment, instincts, and hard work to
solve crimes. This will never change. The information
on which crime analysts’ judgments and instincts are
based, however, can be greatly enhanced with the
availability of effective crime analysis software. The
Regional Crime Analysis Program (ReCAP) developed
by the Department of Systems Engineering at the
University of Virginia is one such tool.
Unfortunately, the current version of ReCAP is
highly specialized to the specific data structure of the
police departments in Charlottesville, Albemarle
County, and the City of Richmond. In order to make
this tool available for use by departments nationwide,
the 1999-2000 Capstone Team has developed an
exportable version of ReCAP. This exportable version,
ReCAP Small Department Edition (ReCAP SDE),
allows smaller departments without an extensive
Records Management System (RMS) to use the
analysis capabilities of ReCAP. ReCAP SDE imports a
single table and performs spatial and statistical analysis
on that data. Additionally, ReCAP SDE requires no
supplementary software.
INTRODUCTION
As the amount of criminal activity across the
country increases, the need for crime prevention also
increases. Therefore police departments need every
available crime-fighting tool that can provide an
advantage over criminals. Since traditional methods of
crime analysis are becoming out-dated due to the
amount of time required for analysis, a more automated
process is desired.
Over the past several years, the University of
Virginia, in conjunction with the police departments in
Charlottesville, Albemarle County, and the City of
Richmond, has developed a Regional Crime Analysis
Program (ReCAP) to understand better when, where,
and how crimes occur. ReCAP integrates a number of
technologies, most notably, database management
systems, statistical and spatial modeling, and reporting
tools into one crime analysis package. The primary
goal of the system is to prevent local crime through
active crime deterrence and increased criminal
apprehension.
The current version of ReCAP is highly specialized
to the specific data structures of the police departments
in Charlottesville, Albemarle County, and the City of
Richmond. In each department, ReCAP is networked
to the department’s RMS, thus requiring the Visual
Basic (VB) code to be specialized. Therefore, this
crime analysis tool is not available to other police
departments in the country, let alone different areas
throughout Virginia.
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Design and Implementation of a Regional Crime Analysis Program: ReCAP SDE
To accommodate smaller police departments and
increase the availability of the crime analysis package
throughout the nation, ReCAP SDE focused on
importing a single file, as opposed to a department’s
entire RMS. The spatial and statistical analysis tools
currently available in ReCAP are also included in the
core functionality of ReCAP SDE. These features,
however, have been altered so no additional software is
needed to run these tools. Additionally, the final
analysis package will be distributed free of charge to
any police department requiring crime analysis tools.
ReCAP SDE will also promote the full version of
ReCAP, which includes reporting features, hot spot
identification, and a tactical analysis tool.
would like to import. This common dialog box only
allows the selection of Microsoft Access, Excel,
FoxPro, dBase, and text files. The file type is identified
and the appropriate provider is used to connect to the
file. If the file type is Access or Excel, the program
then opens another form where the user selects the
desired table name from a list box. Otherwise, the
program proceeds directly to the field matching form
displayed below in Figure 1.
TABLE IMPORTATION
Overview
The strength of ReCAP SDE exists in its ability to
import and analyze tables separate from the police
department’s record management system (RMS). The
program has the ability to import Microsoft Access,
Excel, FoxPro, and text tables. The fields relevant to
the analysis are identified through a simple drag-anddrop interface and saved in an initialization file.
Implementation
The ActiveX Data Object (ADO) Model is designed
to enable programmers to get a set of records from a
data source as quickly as possible. Because speed and
simplicity are two of the key objectives of ADO, it was
perfect to use in ReCAP SDE.
ADO is designed to use Object Linking Embedding
for Databases (OLE DB), which can be thought of as an
alternative to the Open Database Connectivity (ODBC)
method of connecting to data storage. Previously, any
time you wanted VB to access remote databases, you
needed an ODBC interface driver. ODBC uses drivers
to act as translators between VB data requests and the
data store. OLE DB, however, has a property for the
Connection object, called provider. There are several
providers available from Microsoft, but it is this
component that acts as the intermediary between the
VB program and the database. Therefore, there is no
need to install ODBC drivers at setup anymore. Simply
altering a property of the Connection object will serve
the same purpose.
Importing a table for analysis in ReCAP SDE is
accomplished in three separate forms. When the user
selects the table importation feature, a common dialog
box opens and asks them to identify the table they
58
Figure 1: Field Matching Form
The field matching form displayed in Figure 1
works through a simple drag-and-drop methodology.
The “Current Field Names” list box is populated with
the field names from the table. The user merely drags
their field names and drops them in the corresponding
ReCAP SDE universal field name boxes. The program
displays the users’ table to ensure the correct table is
imported, and allows the user to review the information
held in each field. ReCAP SDE has the flexibility to
accept one Date/Time field or two separate fields for
date and time.
After the user’s fields are identified, the “Next”
button is selected and another common dialog box
appears. The user selects a name for the table and the
program saves the table in a recordset (*.rst) file
format. Saving the table as a recordset allows for
minimal disk space and easy manipulation by ReCAP
SDE. In addition, it ensures the users can only open
tables that have gone through the importation process.
While the program saves the recordset, it
simultaneously creates an initialization file that saves
the field matching information. The spatial and
statistical analysis tools access this initialization file to
query the relevant information from the recordset.
2000 Systems Engineering Capstone Conference • University of Virginia
Results
Default Maps
The file importation interface of ReCAP SDE has
the ability to import Access, FoxPro, dBase, Excel, and
text files. Additionally, ReCAP SDE can import very
specific queries, a feature not available in the full
version of ReCAP. This entire capability has already
proven to be a valuable asset. The Charlottesville
Police Department has used ReCAP SDE to import
tables that did not correspond to their current RMS.
Using ReCAP SDE, they were able to import their file
and then analyze the data using the statistical analysis
tools. The analysis allowed the police department to
recognize when more officers are needed to respond to
calls for service.
SPATIAL ANALYSIS
Overview
In addition to the unique relationship with a police
department’s RMS, the existing ReCAP is dependent
upon additional software. The mapping component of
the existing ReCAP is run in MapInfo or ArcView, two
commercially available Geographical Information
Systems (GIS). Such software can be expensive, and
many police departments in the nation or world do not
currently own it. ReCAP SDE eliminates the necessity
for this additional software, without compromising
functionality.
Use of MapObjects
In order to avoid the additional cost to the user of
purchasing an entire GIS software package, ReCAP
SDE utilizes a set of ActiveX controls called
MapObjects. MapObjects (MO) is a dependent
software package produced by the ESRI Corporation
that can be used within Visual Basic. It enables VB
applications to read in various mapping and drawing
file formats for use on a map. MapObjects also allows
the developer to include complex mapping capabilities
without users needing additional software. ReCAP
SDE therefore can create maps independently of GIS
software. Additionally, there are numerous features of
the larger GIS packages that would be of no use to
crime analysts, but ReCAP SDE incorporates only
those functions of value. ReCAP SDE also includes
developer-designed crime analysis tools, such as
layering and clustering.
ReCAP SDE allows users to select which maps are
desired as the defaults. These map layers, such as
streets, bodies of water, and city limits, are likely to be
used for every map produced by analysts. The set-up
process grants analysts the freedom of setting these
important layers once, and then ReCAP SDE draws
them each time a table of crimes is plotted. However,
these layers are not hard-coded in ReCAP SDE and can
be added or removed as desired.
Additionally, users can add, remove, or change the
layers shown even after incidents have been plotted.
Layers such as bus routes, schools, graveyards, and
ABC stores can be added to visually identify patterns in
crime. Users also have the ability to alter the color
schemes of the layers. This ensures that users are not
limited to the default map produced.
Mapping Capabilities
The available features for use within the mapping
window are written using ActiveX commands. In
user’s minds, much of the available functionality
resembles the basic map manipulation tools found in
common GIS software. The mapping features of
ReCAP SDE within the mapping window (shown in
Figure 2 below) include: Zoom In/Out, Pan, Copy to
Clipboard, Radius Select, Rectangle Select, View
Selection, Cluster, Layers, and Print.
Figure 2: ReCAP SDE Mapping Window
59
Design and Implementation of a Regional Crime Analysis Program: ReCAP SDE
The “Zoom In” and “Zoom Out” functions operate
just as the name indicates. Users focus on certain
points defined by them, and then the map screen
transforms to the appropriate magnification, thus
including or eliminating more information. The “Pan”
function allows users to move the map by clicking and
dragging it within the mapping window. A box below
the map object denotes the latitude and longitude of the
cursor as it moves.
The “Copy to Clipboard” button performs the
actions implied by its name. It copies a picture of the
current map held within the map screen to the
computer’s Clipboard. The toolbar, scrollbars, “Close
Map” button, and cursor position are not copied to the
Clipboard.
The “Rectangle Select” and “Radius Select”
functions allow users to select a rectangle shape or
circular shape by the click and drag method. If the
drawn shape encompasses any of the plotted crime
incidents, then users can select the “View Selection”
button. This button calls a function that brings up a
table showing the details of the incidents selected.
ReCAP SDE also includes a “Clustering” function.
Clustering allows users to visualize the criminal
incidents in relation to other incidents. The program
calculates the distance between crimes to identify areas
of high crime.
The “Layers” button allows users to manipulate
what is shown on the map. Layers contain different
geometric and graphic objects such as regions, points,
lines, and text. Users select graphic files that lay on top
of each other to create a working map. Layers then
combine into a picture much like the stacking of
transparencies on an overhead projector would. The
“Layers” button creates a user interface that allows
users to add, remove, or change the color of the layers
that are displayed on the map.
Mapping Results
We tested the Spatial Analysis System implemented
within ReCAP SDE on its functions, speed, and cost to
user. The first test compared the function’s robustness
versus old versions of ReCAP. ReCAP SDE included
all of the functions that the old versions had, and it also
incorporated the layering functionality. Layering had
previously been “hard-coded”, and users were granted
no flexibility in altering their maps. Another test
compared the different loading speeds of the Spatial
Analysis System for the same set of crimes. We timed
how long it took for each program to load and draw
maps for a given number of crimes. ReCAP MapInfo
references the commercial software program MapInfo
60
installed on the local computer. Both ReCAP SDE and
ReCAP (MO) use embedded MapObjects without
additional software. The results are shown in Table 1
below:
Table 1 Loading Times for Mapping of Different
Versions of ReCAP
# of
Records
5
51
62
141
397
# of
Fields
41
41
41
41
41
ReCAP
SDE
2
5
7
16
50
ReCAP
(MO)
12
150
181
465
N/A
ReCAP
MapInfo
4
5
6
7
9
The last test compared the costs of purchasing
needed additional software components. ReCAP SDE
requires the purchase of a MapObjects license, and
ReCAP requires the purchase of a conventional GIS
software package. One MapObjects Deployment
license costs $ 100.00, but ArcView Business Analyst
1.1 with AGS Demographic Data costs $ 11,995.00.
The main success of ReCAP SDE’s mapping
component is the ability to perform spatial analysis
without the necessity of an external GIS. This will
provide police departments nationwide with tools that
were previously unattainable due to prohibitive costs.
STATISTICAL ANALYSIS
Overview
ReCAP SDE provides users with a comprehensive
statistical tool to aid crime analysts in predicting
crimes. The statistical analysis can produce either
temporal or control charts. Temporal analyses show
patterns that develop over different time periods, more
specifically which hours of the day are the most prone
to criminal activity. The control chart is a process
monitor that counts defects at regular intervals and
measures the number of defects against prior rates to
determine the normal statistical variation in the process.
In laymen's terms, control charts are exception
detectors. To plot the incidents on either chart, the date
and time field names are read from the initialization
file. These field names are used to query the recordset
and pull out when each incident occurred.
2000 Systems Engineering Capstone Conference • University of Virginia
Time Charts
The time chart takes these data and plots a 24-hour, a 7day, or a monthly time chart. The 24-hour chart
separates the data into 15-minute intervals for 24 hours,
the 7-day chart separates the data into 2-hour intervals
for 7 days, and the monthly chart separates the data into
8-hour blocks for each day of the month. These data is
put into a corresponding array and plot on a radial curve
or a linear graph. The tool finds any significant values
that fall out of a 3-sigma range, and notifies the user.
Below, in Figure 3, a 24-hour radial display time chart
is shown. The hour 2215 was determined to be a
significant value and therefore police officers might add
more patrolling officers during these hours.
Figure 4: A 52-week control chart
Results
Figure 3: A radial display for a 24-hour time chart
Control Charts
The control chart takes these data and first
determines the most recent date of all the incidents.
Using this date, a previous 52-week analysis is
performed on the data to determine the frequency of
incidents occurring. Each incident is compared initially
if it falls within the 52-week bracket, and then an array
is created that contains the number of incidents for each
week. Using all the data, upper and lower limits are
determined using a normal distribution, as well as the
average number of incidents occurring. All of this is
plotted on a linear graph and any week that exceeds the
upper limit is signaled to the user. Below, in Figure 4,
a 52-week control chart is shown. In week 19, more
incidents than were expected occurred and therefore the
user is made aware of the situation and can increase the
response time to the investigation.
The time and control charts were integrated into
ReCAP SDE to give officers an advantage in their
crime analysis techniques. The time charts provide an
analyst with exact times or days of the week that
historically have proven to be high in criminal activity.
The control charts can offer the community faster
response times by the police by identifying a higher
level of criminal activity than normal.
From a study conducted by Dr. Donald Brown and
Brian Simmons, it was proven that using the statistical
tools, specifically the control chart, increased the
response time to an incident alert by an average of 44
days. The study used actual historical data from the
Charlottesville Police Department. When an alert
appeared from a control chart it was assumed that
action for reassignment would be taken the following
day. However, actual reassignment took a lot longer.
Below in table 2, the results are summarized.
Table 2: Assignment lag time after assignable cause
(Brown, Simmons: 23).
Date of
Alert
Date of
Crime
Date Actual
Assignment
Est. Date of
Assignment
11/19/95
12/3/95
1/28/96
2/25/96
11/15/95
11/30/95
1/24/96
2/21/96
2/2/96
12/21/95
2/5/96
5/13/96
11/20/95
12/4/95
1/29/96
2/26/96
Improvement
(days)
74
19
7
77
Although the study sample is small, it is clear that
control charts can improve response times.
SYSTEM EVALUATION
ReCAP SDE has already been shown
successful in the Charlottesville police department.
Using ReCAP SDE, the department imported a “calls
61
Design and Implementation of a Regional Crime Analysis Program: ReCAP SDE
for service” table exterior to their RMS. The statistical
analysis immediately revealed an out-of-control region
within the data set.
ReCAP SDE proves to be more efficient than
prior versions of ReCAP. The speed of the mapping
element of SDE shows a 20-fold improvement over the
previous stand-alone version of ReCAP (see Table 1).
In addition, the field-matching portion of ReCAP SDE
has proven to be three times faster than ReCAP’s setup
process. The time and control chart analysis features
maintain the same functionality and speed as ReCAP.
Overall, ReCAP SDE has shown marked improvement
and received favorable reviews from the Charlottesville
Police Department.
CONCLUSIONS
ReCAP SDE has many opportunities to impact lawenforcement agencies, citizens, and criminals. ReCAP
SDE provides any community with a speedy crime
analysis tool that can help to track and capture
criminals. File importation provides users with the
flexibility of monitoring sets of data in which they are
most interested, without the necessity of having a large
RMS. In addition, this file importation system allows
police departments to import data from older Legacy
systems. This process is estimated to save $20k per
installation. Statistical analysis tools aid officers in
identifying crime trends more quickly. Finally, spatial
analysis provides officers with a visual aid of hot spots
and crime trends, as well as layering different ideas on
top of each other. Interaction between police
departments and the community would skyrocket,
promoting a sense of security and empowerment.
Patrol routes and areas could be strategically mapped
and coordinated. Technology’s rise would only
improve the functionalities of ReCAP SDE, and it
could benefit any community.
REFERENCES
Brantingham and Brantingham. Patterns in Crime.
New York: Macmillan Publishers, 1984.
Brown, Donald E. 1998. “The Regional Crime
Analysis Program (RECAP): A Framework for
Mining Data to Catch Criminals.” In
Proceedings for the 1998 International
Conference on Systems, MAN, and
Cybernetics (San Diego, CA, USA, Oct. 1114). IEEE, Piscataway, N.J., 2848-2853.
University of Virginia, June 1998.
62
Brown, Donald and Simmons, Brian. “Automatic
Monitoring of Crime Trends Using the C
Control Chart.” University of Virginia.
Gibson, John E. Design of Engineering Systems.
Ivy, VA, July 1991.
Gottlieb, S., S. Arenberg and R. Singh. Crime
Analysis from First Report to Final Arrest.
Alpha Publishing, 1994.
McKean, Tom. Crime Analyst, Charlottesville, VA.
Personal Interviews.
Petroutsos, Evangelos. Mastering Visual Basic 6.
Sybex Inc., Alameda, CA. 1998.
Schnurr, Mike. Crime Analyst. Charlottesville, VA.
Personal Interviews.
BIOGRAPHIES
Grace Curry is a fourth-year Systems Engineering
student from Arlington, Virginia. Her contribution was
in the area of mapping development. Ms. Curry will be
attending Georgetown University in the fall, studying
human physiology and biophysics.
Matthew A. D’Acunto, a fourth-year Systems
Engineering student from Springfield, Virginia,
specializes in Management Information Systems. His
contribution was in the area of table importation and
statistical analysis. Mr. D’Acunto has accepted a job
with Cisco Systems and will be living in New York.
Garland S. Lynn, a fourth-year Systems Engineering
student from Roanoke, Virginia, specializes in
Management Systems. His principle contribution was
in the area mapping development. Mr. Lynn will not be
attending MIT in the fall, but he will travel to Europe in
pursuit of his fortune.
Mark Sameit is a fourth-year Systems Engineering
student from Virginia Beach, Virginia. His
contribution was in the area of table importation and
statistical analysis. Mr. Sameit will be commissioned
as a 2nd Lieutenant in the United States Marine Corps
on May 20th, 2000.