gis crash analysis for beginners: custom applications to assist novice gis users in crash data...

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

Contact Info:

Demian MillerTindale Oliver & Assoc.Tampa, FL813.224.8862

Dmiller@tindaleoliver.com