The purpose of this study was to examine the possible correlates of variability in crime trends over time.
In this logitudinal study a total of 24,023 street segments in Seattle were analyzed. Computerized records of crime incident reports were used to represent crime. Incident reports were generated by police officers or detectives after an initial response to a request for police service. A total of 1,697,212 crime records were joined to their corresponding street segments so that crime frequencies for each of the 24,023 segments for each year could be calculated.
The data collected for the study includes both aspatial (Dataset 1, Seattle Street Segments Aspatial Data) and spatial data (Dataset 2, Seattle Street Centerline Spatial Data and Dataset 3, Seattle Street Midpoint Spatial Data). The spatial data are in ESRI shape file format. Two base files are included that correspond to the units of analysis used in the study. The UofA_lines file contains the vector representation of the street segments in Seattle, Washington, as defined by the study. Only residential and arterial streets were included in the study. Limited access highways were excluded because of their lack of interactive human activity. This left 24,023 units of analysis (i.e., street segments) in Seattle. For this study, the unit of analysis is defined as a street segment (i.e., as both sides of the street between two intersections). The original street centerline file obtained from the Seattle GIS department was edited to make sure each street met the study definition. Each street has a Street_id which is a unique identifier. The UofA_points file contains the mid-points of all the street segments. This shape file also contains a Street_id field which is a unique identifier. The aspatial data file can be joined to either the line file or the point file using the Street_id field.
The geographic unit of analysis for this study is the street segment (sometimes referred to as a street block or face block). The street segment was defined as both sides of the street between two intersections. Only residential and arterial streets were included in the study. Limited access highways were excluded because of their lack of interactive human activity, leaving the school with 24,023 units of analysis (i.e., street segments) in Seattle.
Street segments in Seattle, Washington.
Street segment: both sides of the street between two intersections.
Seattle Public Libraries
Seattle School District
Seattle Public Schools
Seattle Public Utilities
InfoUSA database of all businesses in Seattle
Fleets and Facilities Department, City of Seattle
Labels and Lists Inc. (voter registration)
Seattle Planning Department and parcel boundaries King County GIS
Department of Transportation (Metro Transit Division)
administrative records data
The study contains 103 variables including crime information, social disorganization information and measures representing opportunity theories. Crime count information included crime counts in Seattle for each year between 1989 and 2004 and moving averages for crime rates in the first (1989-1991) and last (2002-2004) three years. Social disorganization information included property value, housing assistance, race, truant student residents, voting behavior, unsupervised teens, physical disorder, and urbanization. Measures representing opportunity theories included high-risk juvenile residents, location of public facilities, number of public facilities, street lighting, public transportation, street networks, land use, and business sales.