Best Practices in Transit Rider Survey Data Collection Chris Tatham

Best Practices in Transit Rider Survey Data Collection

Chris TathamSr. Vice President, CEO, ETC Institute

725 W. Frontier CircleOlathe, KS 66061

[email protected]

January 25, 2012

Challenges with Rider Survey Data Collection

Methods to Address These Challenges

◦ Closely Manage the Design & Distribution of the Sample

◦ Use Tablet PCs & Personal Interviews

◦ Carefully Plan and Conduct Data Expansion

Summary

Questions

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Inadequate Development and Management of the Sample◦ Sampling plans are often developed using very

little information on ridership Usually limited to the total average ridership on a

bus route or rail station, but little else is known◦ Distribution of the sample is often not monitored

while in the field Surveys are collected and the distribution is

reviewed after the survey has been completed◦ IMPACT: Samples are not representative of

the ridership

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Very little effort is taken to gather data

to support sample-expansion◦ Ride check data is usually available, but seldom

reviewed before surveys are conducted Inattention to automated counts misses a huge (and

largely free!) opportunity Major stops along a route are under-represented End-of-the-Line locations are over-represented

◦ Vehicle counts from P&R lots are available, but often not used – could provide as control totals for data expansion

◦ IMPACT: Aggregate expansion only magnifies sampling errors

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jr

Maybe "Inadequate Data and Methods for Sample Expansion"Problem is both data and methods -- and I'm not sure which is the primary cause, kind of like the chicken and the egg

Severe attrition with self-administered surveys handed out to transit riders

◦ Low participation rates◦ Biases in the types of people who respond◦ High rates of incomplete/illogical records◦ High rates of geo-coding failure◦ IMPACT: introduction of unknown biases

related to ridership characteristics and travel patterns

Response rates are often less than 20% andA Majority of the Completed Surveys

A Often Unusable6

Assemble data on existing ridership (first!)◦ Obtain counts from APCs, faregates, etc.◦ Undertake manual boarding/alighting counts if necessary◦ Consider on-to-off “survey”

Set Detailed Sampling Goals:◦ Don’t stop with aggregate goals for each route/station◦ Set goals for:

specific locations along each route specific types of trips (Station A to B/Stop A to B by time of day by direction

Manage the goals while you are in the field

1. Closely Manage the Design & Distribution of the Sample

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GPS Based ScannersCaptured More than

97% of the

On-to-Off Flows in Honolulu

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Advantages of Personal Interview◦ More accurate ◦ More complete◦ More representative

key groups are not under-represented

Advantages of Tablet PCs◦ Details about the study area/transit system can be

pre-programmed◦ Can be programmed to interface with Google-Maps for

real-time geocoding in the field ◦ Manage sample distribution in the field◦ Real-time management of data collection in the field

with IPad w/3G◦ Less time to administer (helps capture short trips)

2. Use Tablet PCs & Personal Interviews

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Combined results of pilot tests in Atlanta (2009), Phoenix (2010), and Nashville (2011)

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01

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Options Presented at the Beginning of the Survey

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08aSurvey Interfaces with Google-Earth in Real-Time

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13aKey Locations, such as Park and Ride Lots Are

Preloaded

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15Bus Route Shape FilesAre Integrated

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Route Transfers Are Limited

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25Summary ScreenEnsures All Recorded Information Is Correct

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Reasons Tablet PCs Enhance Data Quality and Sampling

Video Demonstration

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Control sample expansion at the least aggregate level possible◦ Ensures the proper distribution of trips along routes◦ Limited by density of samples at stops/stations◦ Often involves some aggregation of stops/stations

Better data supports better expansion: ◦ Atlanta rail faregate data station-to-station controls◦ Atlanta bus APC data stop-on and stop-off controls◦ Phoenix rail counting task (ons, offs, on-to-offs)

station-to-station controls Without good control totals you can’t ensure that

your expanded data are representative

3. Carefully Plan and Conduct Data Expansion

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RTE 17 DESIRE LINES FROM ON => OFF COUNTS OCT 2011 – ALL FLOWS

Good On-to-Off Flow

Data Helps PlanFor Data Expansion

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Simple Example of Data Expansion - RAIL

Table 1: NUMBER OF COMPLETE/USEABLE SURVEY (PM PEAK 3-7 PM)WHERE GET OFF

S7 N5 W3 E7 P1WHERE GET ON

Airport Arts Center Ashby Avondale Bankhead TOTALS7=Airport 0 7 3 4 2 16N5=Art Center 9 0 2 4 1 16W3=Ashby 3 2 0 2 14 21E7=Avondale 4 3 2 0 1 10P1=Bankhead 3 3 2 2 0 63

Table 2: FARE GATE COUNTS BY STATION OF ENTRY AND EXIT (PM PEAK 3-7 PM)WHERE GET OFF

S7 N5 W3 E7 P1WHERE GET ON Airport Arts Center Ashby Avondale Bankhead TOTALS7=Airport 0 115 10 49 9 184N5=Art Center 116 0 21 58 11 207W3=Ashby 16 21 0 8 32 77E7=Avondale 42 29 14 0 9 94P1=Bankhead 8 6 28 6 0 562

Table 3: EXPANSION FACTORS/MULTIPLIERS ( PM PEAK 3-7 PM)WHERE GET OFF

S7 N5 W3 E7 P1WHERE GET ON Airport Arts Center Ashby Avondale Bankhead TOTALS7=Airport #DIV/0! 16.480356 3.329365 12.235416 4.619494 11.470702N5=Art Center 12.901289 #DIV/0! 10.737202 14.607588 11.236606 12.953310W3=Ashby 5.493452 10.362648 #DIV/0! 3.995238 2.265157 3.662301E7=Avondale 10.425074 9.738392 6.991666 #DIV/0! 8.989285 9.388809P1=Bankhead 2.746726 1.914385 13.858481 3.121280 #DIV/0! 8.913978

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If You Don’t Manage Your Sample, Your Data Could Look Like This

Table 1: NUMBER OF COMPLETE/USEABLE SURVEY (PM PEAK 3-7 PM)WHERE GET OFF

S7 N5 W3 E7 P1WHERE GET ON

Airport Arts Center Ashby Avondale Bankhead TOTALS7=Airport 0 1 0 6 9 16N5=Art Center 4 0 0 1 11 16W3=Ashby 14 0 0 0 7 21E7=Avondale 0 9 0 0 1 10P1=Bankhead 0 3 2 2 0 63

Table 2: FARE GATE COUNTS BY STATION OF ENTRY AND EXIT (PM PEAK 3-7 PM)WHERE GET OFF

S7 N5 W3 E7 P1WHERE GET ON Airport Arts Center Ashby Avondale Bankhead TOTALS7=Airport 0 115 10 49 9 184N5=Art Center 116 0 21 58 11 207W3=Ashby 16 21 0 8 32 77E7=Avondale 42 29 14 0 9 94P1=Bankhead 8 6 28 6 0 562

Table 3: EXPANSION FACTORS/MULTIPLIERS ( PM PEAK 3-7 PM)WHERE GET OFF

S7 N5 W3 E7 P1WHERE GET ON Airport Arts Center Ashby Avondale Bankhead TOTALS7=Airport #DIV/0! 115.362492 #DIV/0! 8.156944 1.026554 11.470702N5=Art Center 29.027900 #DIV/0! #DIV/0! 58.430353 1.021510 12.953310W3=Ashby 1.177168 #DIV/0! #DIV/0! #DIV/0! 4.530314 3.662301E7=Avondale #DIV/0! 3.246131 #DIV/0! #DIV/0! 8.989285 9.388809P1=Bankhead #DIV/0! 1.914385 13.858481 3.121280 #DIV/0! 8.913978

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• The Tablet PC/Personal Interview method facilitates data expansion, which can lower the overall unitcost per completed useable survey

Location Year Method

Survey Administration

Cost*

Complete Useable Surveys

Unit Cost Per Useable Survey

Atlanta 2010 Tablet PC/Interview 1,624,300$ 43200 37.60$ Phoenix 2011 Tablet PC/Interview 618,500$ 15450 40.03$ Nashville 2011 Tablet PC/Interview 165,000$ 3956 41.71$ *Survey Administration Costs Do Not Include Survey Design, Sampling Plan, Pilot Test, Analysis, etc

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The methods discussed today can be used to enhance the overall quality of the data collected

Closely Manage the Design & Distribution of the Sample

Use Tablet PCs & Personal Interviews Carefully Plan and Conduct Data Expansion

Take advantage of new technology Give yourself enough time to do the survey right Good training and oversight of the people

administering the survey is always essential.

Summary

Improvements in the quality of survey datawill place pressure on transit agencies to collect

better ridership data 26

Chris TathamSr. Vice President, CEO

ETC Institute725 W. Frontier Circle

Olathe, KS 66061913-254-4512

[email protected]

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Best Practices in Transit Rider Survey Data Collection Chris Tatham

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