gis crash analysis for beginners: custom applications to assist novice gis users in crash data...
TRANSCRIPT
GIS Crash Analysis for Beginners:Custom Applications to Assist Novice GIS
Users in Crash Data Analysis
GIS Analysis Tools
Performs Standard Queries – Normalize Data– Reduce Errors
Allows Data Query To Follow On Spatial Selection/Association
Provides Common Dbf IV Output Table
Standardize Queries Normalize Data
– Many Crash Data Questions Examine Multiple Fields
– Allows User Without Relational Database Management Skills to Review Complex Data
Reduce Error– Canned Queries Assure Desired Result
– Two Analysts Will Arrive At Same Conclusion
“Nest” Queries– Allows User to Sequence Multiple Queries for Complex
Analysis1. Pedestrian
2. + Bicycle
3. Night
4. Fatal or Severe Injury
Select a Standard Query
Defines Query
Nest Query
Select “or” Query
Add Bicycle Crashes to Selection
Defines Query
Select “and” Query
Automatic Population of ‘Drop-Down’
Select Fatal Crashes From
Selection
Convert Query Results to Map
‘Theme’
Review Summary Data for a Specific
Event
Retrieve Scanned Crash
Report
Spatial Selection/Data Association
Select Crashes Manually Using Built-in Tool
Use ‘Overlay’ Capability to Select Crashes– Proximity to Schools– Specific Neighborhoods/Planning Areas
Correlate Spatial Attributes with Crash Data– Vehicle per Household vs. Bike/Ped Crashes– Roadway Classification
Common DBFVI File Format
Opens Easily in Excel or MS-Access
Macros or VBA Allow Quick Chart and Report Production– Frequency by Attribute Charts
Supply Data to Clients in Common Format
Figure II-d: First Harmful Event
0.0% 10.0% 20.0% 30.0% 40.0% 50.0%
Rear End
Left Turn
Backed Into
Pedestrian
Tree/Shrubbery
Other
State of Florida
Pasco County
US 19
Analysis based on 1999 to 2001 DHSMV Database. US 19 2,238 records; Pasco County
Compare Corridor to State/County
Compare Corridor to State/County
Figure II-e: Crash Injury Severity
0.0% 10.0%
20.0%
30.0%
40.0%
50.0%
No Injury
Possible Injury
Non-Incapacitating Evident Injury
Incapacitating Injury
Fatal Injury
State of Florida
Pasco County
US 19
Analysis based on 1999 to 2001 DHSMV Database. US 19 2,238 records*; Pasco County 11,856 records; State of Florida 746,119 records
First Harm
0% 10% 20% 30% 40% 50% 60% 70%
Collision w ith MV in Transport (Rear-end)
Collision w ith MV in Transport (angle)
Collision w ith MV in Transport (Left Turn)
Collision w ith MV in Transport (Sidesw ipe)
Collision w ith MV in Transport (Backed Into)
Collision w ith Parked Car
Collision w ith Pedestrian
Colision w ith Bicycle
MV Hit Tree/ Shrubbery
MV Ran Into Ditch/ Culvert
Other
State of Florida
US 19
Trouble Creek Road
* Percentage for Right Turn Crashes on Trouble Creek Road is 6%.
Compare Intersection to Corridor/State
