Auditing GIS Data Proving What You Have Indiana GIS Conference February 2010

Overview Decide on what you want to verify Identify/Establish Accuracy Standards Techniques for verifying data Techniques used in the KY Geospatial audit Issues discovered Options implemented for correction Benefits of self audit

What’s Important? The most important components of a GIS are people. Trained people, who understand GIS as well as E9-1-1, play a vital role in a successful GIS. People, who create and maintain the data as well as those who use the GIS are key to successful E9-1-1 implementation. The procedures, processes, and techniques these people use in developing and using a GIS are critical to reaching an informed decision.

What’s Important No matter where you get your data, you have to assume responsibility for the accuracy, completeness, and currency of the data. The map data must agree with the MSAG data, otherwise the ALI will not display the correct information on the visual map. A Public Safety Answering Point Managers’Guide to Geographic Information Technology, A National Emergency Number Association White Paper, October 2002

What to Test General GIS data –Geocoding accuracy –Centerline accuracy Wireless information –Is the right information being provided? –How accurate is that information? Both

Standards? What Standards? Geocoding Accuracy –How close does it need to be? –State or local choice –In Kentucky geocoding results shall be accurate to within 0.1 mile Centerline Accuracy –Accurate representation of the roadway? –How close does it need to be?

Standards? What Standards? Wireless data standards –FCC Standards are based on a national view Network Based Location Solutions –95% of the time <= 300 meters (984 feet) –67% of the time <= 100 meters (328 feet) Handset Based Location Solutions –95% of the time <= 150 meters (492 feet) –67% of the time <= 50 meters (164 feet)

Local Standards Identify or establish what you will use locally. –National, state, local. –Treat it like a law, you may be stricter than the higher jurisdiction but never less. Document the accepted standards. –Makes it easier to repeat the process. –Makes it easier to compare results and measure improvement.

Kentucky Geospatial Audit Authority The Commercial Mobile Radio Service Emergency Telecommunications Board (CMRS Board) is charged with administrating the CMRS fund for the purpose of implementing wireless emergency Enhanced 911 service throughout Kentucky in accordance with State and Federal Legislation and Regulations.

202 KAR 6:100 (4) Each PSAP's mapping shall be tested for the accuracy of road centerline data. A minimum of twenty (20) randomly-selected address points shall be tested in each PSAP response area. If a PSAP response area encompasses multiple counties, a sampling of a minimum of twenty (20) randomly- selected address points per county shall be tested. Tested locations shall: (a) Be distributed across the PSAP response area to yield a valid cross section of urban and rural environments; (b) Plot on the correct side of the street as shown on the base map data supplied by the PSAP; (c) Plot within the correct cross streets as shown on the base map data supplied by the PSAP; and (d) Plot within one-tenth (1/10) of a mile of their location on PSAP supplied base maps.

Standards Influence the Process and Techniques 20 random points –Process to generate 20 random points through out the jurisdiction. –Distributed between urban and rural. Think incorporated and unincorporated Think city and township Hawth Tools –Generate 20 points per county –Generate 3 points per incorporated area –Snap to centerlines –Random selection of 20 final points from combined set

Standards Influence the Process and Techniques Data must plot within certain parameters to supplied data –What elements should be compared? Field collected points both XY and field collected addresses –Using GPS equipment Navigate to the random point Identify the nearest posted address and record address Take a GPS fix of the driveway or actual structure Repeat as necessary

Standards Influence the Process and Technique

Equipment used: –ArcView with Network Analyst –Trimble GeoXT with external antenna –ArcPad 7.x on laptop –Digital camera –Access

Overview of the Initial Kentucky Audit Collected data in 120 counties and 5 additional PSAP jurisdictions 2666 data points collected Teams traveled more than 13,000 road miles

Overview of the Initial Kentucky Audit

Applying the Standards Test collected data –Test in the dispatch office with the data being used there and the mapping solution being used. Discoveries –46% of the field data points failed the standards. –GIS data not necessarily the same as in the dispatch office. Out of date data in dispatch More current in dispatch center –Mapping solutions did not display data according to the standards. Did not offset to left or right of centerline segment Introduced rounding errors that reduce accuracy Would not accept LAT LONG entry

Results of 1 st part of Geospatial Audit PSAPs that passed –Very involved in address assignment and GIS data maintenance –Active communication and data exchange between governmental agencies and emergency services –Proactive on data verification and validation

Results of 1 st part of Geospatial Audit PSAPs that did not pass –Reviewed results and created a correction plan Data improvement Software/hardware updates and changes –Improving communication and data exchange –All PSAPs re-audited have passed showing significant improvement in data and function

Correction Plans Update, upgrade, change mapping solution –Several software issues were corrected by the vendors of the CAD/Mapping solutions. Update, correct, rebuild GIS data –Scrub and correct all segment ranges reflecting actual ranges and not theoretical ranges –Develop point address layer

Wireless Data Audit Criteria (3) Audits shall verify that upon receipt of a wireless 911 call the PSAP's mapping component shall: (a)1. Display the X, Y coordinates on digital base maps used by the PSAP; 2. Identify the incoming 911 call on the map display; and 3. Identify the closest assigned address to the X,Y [of the caller] coordinates provided; or (b) In the absence of the X, Y coordinate information, [of the caller] identify the cell site, and cell-face. [CMRS interpretation is that it should be done automatically upon receipt of the call]

Why this Criteria? Currently the majority of wireless calls are routed to PSAPs based on tower face. Next Generation (NG9-1-1) will incorporate routing based on X, Y.

Tower Sectors Most Towers are divided into “faces” or “sectors” Each has a unique routing number and should have a unique address entry. 123 Any St – NW 123 Any St – E 123 Any St – SW pANI/ESRD/ESRK directly related to cell face/sector

Tower Sectors

Wireless Audit Function or accuracy or both If accuracy, consider auditing the accuracy of the data provided with the intent of fully understanding the capabilities of the current implementations. –Do not expect to take the data and bring about change in the wireless carriers

Wireless Audit Approach #1 – Analysis of data captured at the PSAP –Run a report for wireless calls that are related to a specific street address. –Plot distribution of the X, Y data provided. –Compare the X, Y data provided with the address data. Test if it meets the wireless criteria.

Wireless Audit Approach

#2 – Field data collection –Navigate to random addresses similar to the approach described earlier –Make test calls –Compare the collected X, Y with the address

Wireless Audit Findings Some Phase II calls acted as Phase I calls –X, Y was of the receiving tower –X, Y did not change with rebid Large variance in location accuracy –Issues based on system being used –Some very accurate –Some very inaccurate

Benefits of a GIS Audit Opportunity to get more people involved Identifies areas for improvement Provides a better product A better product means better service

Questions? James Morse GIS Project Manager Stantec Consulting Services Inc Nelson Miller Parkway Louisville, Kentucky Ph: (502) Fx: (502) stantec.com