Embed Size (px)
Citation preview
SHRP 2 Traveler Information and Travel
Reliability (L14)
SHRP 2 Tuesdays Webinar Series
August 26, 2014
2
The Transportation Research Board has met the standards and
requirements of the Registered Continuing Education Program.
Credit earned on completion of this program will be reported to
RCEP at RCEP.net. A certificate of completion will be issued to
each participant.
As such, it does not include content that may be deemed or
construed to be an approval or endorsement by RCEP.
Today’s Learning Objectives
At the end of this webinar, participants will be
able to:
• Identify efficient methods to introduce public awareness
and understanding of the variability of travel time;
• Identify effective terms to convey travel time reliability
information to travelers; and
• Identify efficient methods to communicate travel time
reliability information to be understood and used by road
travelers.
3
PDH Certificate Information
• This webinar is valued at 1.5 Professional
Development Hours (PDH).
• Instructions on retrieving your certificate will be
found in your webinar reminder and follow-up
emails.
• You must register and attend as an individual to
receive a PDH certificate.
• TRB will report your hours within one week.
• Questions? Contact Reggie Gillum at
4
All Attendees Are Muted
5
Questions and Answers
• Please type your
questions into your
webinar control panel
• We will read your
questions out loud, and
answer as many
questions as time allows.
6
Can’t find the GoToWebinar Control
Panel?
7
Panelist Presentations
http://onlinepubs.trb.org/onlinepubs/webinars/140826.pdf
After the webinar, you will also receive a
follow-up email containing a link to the
recording
Today’s Panelists and Moderator
• Beverly Kuhn, Texas A&M Transportation Institute [email protected]
• Vaishali Shah, Noblis [email protected]
• Jimmy Chu, Federal Highway Administration [email protected]
• Bill Hyman, Transportation Research Board [email protected]
9
10 TRB’s SHRP 2 Tuesdays Webinar – August 26, 2014
– $232 million, federally funded research program to
address critical transportation challenges
• Making highways safer
• Fixing deteriorating infrastructure
• Reducing congestion
– Managed by TRB of the National Academies
– Collaborative effort of TRB, AASHTO, and FHWA
– Originally operates from 2006 to 2013 – extended to
2015
– Aims to advance innovative ways to plan, renew,
operate, and improve safety on the Nation's highways
WHAT IS SHRP2 ?
FOUR RESEARCH
FOCUS AREAS
Safety: to prevent or reduce the severity of highway
crashes by understanding driving behavior.
Renewal: to renew aging infrastructure through rapid
design and construction methods that minimize
disruption and produce long-lived facilities.
Capacity: to integrate mobility, economic,
environmental, and community needs into the planning
and design of new highway capacity.
Reliability …. How travel time varies over time…….
Reliable Travel Time
Better Transport Decisions
Safe Highways
Rapid Renewal
and Lasting
Facilities
FOCUS AREAS
Reliability
Capacity Renewal
Safety
All
affect
Reliabili
ty
CONGESTION
Capacity Research Tackles recurring congestion
Reliability Research Tackles nonrecurring congestion
RELATION OF CAPACITY
AND RELIABILITY RESEARCH
RELIABILITY FOCUS AREA
OBJECTIVE
“To provide reliable travel times by preventing and reducing non-recurring congestion”
•i.e., reduce the variability of travel time through reducing the underlying causes
THE SEVEN CAUSES
OF UNRELIABILITY
The Reliability Focus Area research has attributed
variability in travel time to seven primary causes
1. Incidents
2. Weather
3. Work zones
4. Fluctuations in demand
5. Special events
6. Traffic control devices
7. Inadequate base capacity
RELIABILITY,
A NEW FOCUS
Travel Time
Past focus only on
Average Travel Time
Now focus is also on
Variability/Reliability
Probability
AVG
SHRP2 TUESDAYS
Upcoming Webinars
September 9 – “Local Methods for Modeling, Economic Evaluation,
and Travel Time Reliability in Transportation Decision Making
(L35)”
September 16 – Incorporating Reliability Performance Measures in
Operations and Planning Modeling Tools (L04)
18
Learn about future webinars at
www.TRB.org/SHRP2/webinars
SHRP2 L14
EFFECTIVENESS OF DIFFERENT
APPROACHES TO
DISSEMINATING TRAVELER
INFORMATION
ON TRAVEL TIME RELIABILITY
SHRP2 L14 Webinar – August 26, 2014
Beverly Kuhn, TTI
The SHRP2 L14 Project
Context
21
Uses of reliability information by transportation
profession.
Mobility performance measures.
Planning and project prioritization.
Transit system performance monitoring.
Context
22
Use of reliability information by system users.
Trip planning for habitual trips when new to an area.
Pre-trip planning information immediately prior to
departure.
En route prior to a route or mode choice point.
L-14 Project Objectives
23
Provide agencies with tools to expand the uses of
reliability information to.
Communicate with policy makers.
Communicate with system users.
Develop lexicon of terms or “phrase book”.
Update Valuation ($$) of Reliability information in
Utility Functions.
Document research results.
Lexicon
• What is reliability information?
• How does it differ from real-time traveler information?
• How can reliability information be conveyed?
• How can the impacts of reliability information be valued?
• What forms of reliability information are most effective?
Innovation Scan, State of Practice Report, Expert Interviews
Focus Groups/ Surveys Precursor Experiment
Expanded Experimentation
Definition of travel time reliability information
Current forms and media for reliability information
Evaluation methodology
Serenity-sensitive utility function
Preferred terms
Alternative media
Evaluated forms and terms
Valuation of reliability info
Pha
se 1
:
Foun
da
tional Rese
arc
h
Pha
se 2
:
Focu
sed
Exp
eri
ments
SHRP2 L14: RELIABILITY INFORMAITON GUIDEBOOK DEVELOPMENT
9
Reliability Information
25
Reliability information describes underlying trip
variability and includes other contextual data
travelers use to manage on-time performance, e.g.:
Information describing the statistical variation in travel time
dependent on departure time choice.
Data describing on-time performance and lateness risk by
route, mode and destination.
Contextual information to interpret cueing throughout the
travel experience allowing travelers to better assess travel
time and lateness risk both pre-trip and en route.
Examples of Reliability Information
as communicated “person-to-person”
26
Statistical variation in travel times.
To get to the airport at 3 PM, normally it will take 45 minutes, but you’d
better plan for 75 minutes just in case.
If you wait until 4 PM to leave, then plan for at least 2 hours.
Lateness risk descriptions.
Budgeting only 60 minutes between these two meetings? You’ve got a 50-
50 chance of arriving before we start without you.
Contextual information to interpret real-time cueing.
If you find traffic backed up to Exit 4, then you know you’ve got at least
another 30 minutes to go.
Interplay between Reliability and Real-
Time Information in Decision Making
27
My last trip was
about an hour
MY
EXPERIENCE
REAL-TIME
INFO/CUEING
The last traffic report
didn’t mention the
freeway I use
HOW LONG SHOULD I EXPECT THIS TRIP TO TAKE?
RELIABILITY
INFORMATION
Great Day: 35 min
Good Day: 40 min
Bad Day: 75 min
*XDOT 6mo archive
Reliability Information has Highest
Influence When Trip Experience is Low
28
I have never taken
this trip before
MY
EXPERIENCE
REAL-TIME
INFO/CUEING
What radio station
carries traffic
information?
HOW LONG SHOULD I EXPECT THIS TRIP TO TAKE?
RELIABILITY
INFORMATION
Great Day: 35 min
Good Day: 40 min
Bad Day: 75 min
*XDOT 6mo archive
(weak)
(weak) (strong)
Key Research Issues
29
Do travelers want this information?
Do they understand reliability separate from real-time information?
Do they understand concepts of average and variability?
What terms can be used to communicate these concepts?
Can travelers assign a dollar cost value to reliability information?
Is there a role for reliability information in real-time systems?
Key Research Issues
30
Do travelers want this info pre-trip or en route?
Does their desire for info change as function of trip
purpose, route, constraints?
Do they want push or pull information systems?
How can multiple data source be displayed?
Will travelers change their habitual travel patterns
based on reliability info?
Lexicon / Report
• What is reliability information?
• How does it differ from real-time traveler information?
• How can reliability information be conveyed?
• How can the impacts of reliability information be valued?
• What forms of reliability information are most effective?
Innovation Scan, State of Practice Report, Expert Interviews
Focus Groups/ Surveys Precursor Experiment
Expanded Experimentation
Definition of travel time reliability information
Current forms and media for reliability information
Evaluation methodology
Serenity-sensitive utility function
Preferred terms
Alternative media
Evaluated forms and terms
Valuation of reliability info
Pha
se 1
:
Foun
da
tional Rese
arc
h
Pha
se 2
:
Focu
sed
Exp
eri
ments
SHRP2 L14: RELIABILITY INFORMAITON GUIDEBOOK DEVELOPMENT
9
Focus Groups – Key Findings
32
General interest in using information and felt it could be helpful.
Route options and mobile alerts.
Pre-trip tool, not en route.
Occasional use, especially for unfamiliar trips, cities.
Not seen as beneficial for unconstrained trips.
Difficult to convey reliability concept.
Generally unwilling to pay.
Computer Survey – Key Findings
33
Most have a desire for information that a planned trip has a chance of taking longer than average.
“Average” and “95th percentile” not clearly understood by many participants.
Most participants will add time to a total trip time estimate, even if it already includes a buffer time.
Mode reliability information needs to be provided to have any effect on mode choice.
Showed preference for various terms for website interface (future trip, predict/plan trip, best route, recommended departure time, etc.).
Open-ended Survey – Key Findings
34
Buffer Time
No clear preference when assessing how participants determined trip time.
Terms “recommended cushion time” and “cushion time” selected most frequently.
May be difficult to get people to accept trip uncertainty less than they are used to experiencing.
Total Trip Time
“Majority of the time” yielded the best selection of a time to represent the 95th percentile time.
“Most of the time” also fared well.
Lower the uncertainty time, the less trusted by participants.
Decreases workload of driver – don’t have to calculate.
Open-ended Survey – Key Findings
35
Comparison of Travel Time Uncertainty.
Most recognize “buffer time” or “total trip time” as an
upper limit.
Slight preference for “total trip time” over the use of
buffer terms.
Normal Travel Time
No clear preference among various terms tested –
estimated, expected, average, typical.
Any may be use to convey normal travel time.
SHRP2 L14 – Phase II
Usability Testing and Survey
Experiments
Vaishali Shah
26 August 2014
37 37
Review - Why Reliability Information?
The value of real-time information is evident for
routine daily trips
• You already know what to expect on normal days
• You need to know if something is different
Reliability information is more nuanced and
valuable in commute & non-commute decisions
• How much time should I budget? I can’t be late!
• How bad might it be if I move our a little further into
the suburbs? Inrix Traffic (2009)
Reliability info focuses on conveying historic travel time variation
• Trip-based typical versus ‘bad’ ranges in travel time by time of day, day
of week, weather condition, etc..
• Based on historic data of travel times along with event data that is
route-specific
38 38
Scope & Purpose - Experiments
Develop and apply simulation test environment with travelers that
predominantly use the auto in order to:
• Assess comprehension of and preference for reliability terms
• Test user acceptance of reliability terms
• Examine information use, serenity benefits, perceptions of usefulness,
actual usefulness, and swiftness of personal historical framework
Phase I - Exploratory Phase II – Refinement & Confirmation
39 39
Two Experiments – One Platform
Precursor Experiment – identify relative value (perceived and
‘observed’) for reliability information where real-time information is
available
Focused Experiment – two components to the experiment
• Identify and compare the usefulness of different levels of reliability
information using audio, text, and graphic delivery method
• Follow on to precursor experiment for learning behavior
40 40
Precursor Experiment Hypotheses
Provision of accurate reliability
information will result in improved
on-time performance and lower
generalized travel disutility
Benefits of reliability information
will decline as subjects become
familiar with travel time variability
There is a “serenity benefit” to
traveler information
The perceived value of the
reliability information will lag
realized benefit.
80 participants in 5 US cities
3 levels of additive information– either DMS, real-time, reliability
10 commutes = 2 work weeks
3 departure time options
Two decision points for route diversion
41 41
Precursor Experiment Outcomes
Reliability information did affect departure time decisions and did benefit
unfamiliar time-constrained travelers
2 weeks is insufficient for travelers without reliability information to
internalize trip variability and perform at par with those having reliability info
Serenity benefit of traveler information measured – value of knowing you
will be late
Perceived value trailed
observed value
42 42
Focused Experiment Hypotheses
Provision of reliability information improves on-time performance
versus a control group that receives no reliability information
• Some information forms will be more effective than others
• Perceived benefit will trail actual benefit
Experiment #2a –Compare decisions and outcomes for different forms
and content of data presented to unfamiliar travelers
Benefits of reliability information will decrease over time as
participants build a larger experience base
Experiment #2b – Compare the learning curve for unfamiliar travelers
with or without reliability information
43 43
Focused Experiment:
Many Reliability Terms, Test 7 Terms Quantitatively
A. Baseline radio information presented textually (no reliability)
B. Text-based 95th percentile
C. Text-based average plus 95th percentile
D. Text-based 20th, average, and 95th percentile
E. Reliability Signposting
F. Graphical “C”
G. Graphical “D”
H. Auditory “B”
Sample terms assessed in focus group and usability testing (Phase I)
44 44
Efficient Experimental Design Planning
Pairwise testing of seven reliability terms untenable; Experimental
design enabled statistically significant outcomes 1500 >> 240
participants
45 45
Participant Characteristics
250 paid participants in 3 Major Cities - Washington DC, Houston
TX, and Chicago IL, 90-minutes engagement, presented as a game
• More educated sample than population at large
• Older sample population than population at large
• Definition of Late Arrival
46 46
Participant Demographics
47 47
Information and Road Use Characteristics
48
Experiment Screen Shots
Focus Experiment
SHRP2 L14 – Phase II
49 49
Beginning of Experiment
50 50
Participants’ Pre-Trip Decisions
*When participant clicks box, trip information box appears to the right of the screen
51 51
A. Baseline radio information presented textually
52 52
B. Text-based 95th percentile
53 53
C. Text-based average plus 95th percentile
54 54
D. Text-based 20th, average, and 95th percentile
55 55
E. Reliability Signposting
56 56
F. Graphic Presentation of Avg + 95th
57 57
G. Graphic Presentation of Good, Typical, Bad
58 58
H. Auditory 95th percentile data
59 59
Participants’ Post-trip decision
60 60
Participants End-of-week Questions
61
Experiment Findings
Focus Experiment
SHRP2 L14 – Phase II
62 62
Place Your Bets…
Which one proved most effective?
Which one did traveler feel was most effective?
63 63
Detailed Pairwise Comparison – 95th Percentile
Comparison of Participant Response Text 95th Percentile vs. No Reliability Information
Metrics (123 sample size) Control Text 95th Stat. Sig.
Trip
Outc
om
es Average Early Schedule Delay (minutes) 14.4 17.5 100%
Average Late Schedule Delay (minutes) 6.9 6.3 93%
Frequency of Late Arrivals (1-5) 1.4 0.9 100%
Week's Schedule Offset Costs $48.01 $37.98 100%
Pre
-Trip
Sele
ctio
n
Avg Dep Time Selected (1=earliest, 7=latest) 3.7 2.9 100%
Avg OTA confidence (1=not, 5=very) 3.4 3.6 100%
Avg Pre-Trip Usefulness (1=not, 5=very) 3.0 3.4 100%
Post-
Trip
Valu
atio
n
Avg Willingness to Pay ($/trip) $2.51 $2.67 96%
Avg Post Trip Usefulness 2.7 2.5 97%
Avg Post Trip Stressfulness 2.7 3.2 100%
End o
f W
eek
Valu
atio
n
Reduce Stress (5=absolutely) 3.0 3.3 99%
Usefulness ( 5=very useful) 3.1 3.4 99%
Manage Departure Decisions (5=absolutely) 3.2 3.4 91%
Difficulty in Understanding Info (5=very difficult) 2.1 2.1 Not S.S.
Willingness to Pay ($/trip) $2.78 $2.68 Not S.S.
64 64
Focused Experiment 2a - Comparing Delivery Media
Text v. Auditory 95th Percentile Reliability Information • No statistically significant differences for trip outcomes or valuation
• Text rated slightly more difficult to understand compared to auditory
Text v. Graphic - Average + 95th Percentile Info • Generally no statistically significant differences for trip outcomes and
valuation with the exception of reducing stress
Text versus Graphic 20th, Average and 95th Percentile • Text data resulted in lower schedule offset costs
• Text data allowed participants to better manage their trip decisions
Schedule offset costs Days Late
65 65
Focused Experiment 2a - Post Survey
Survey response on usefulness and complexity of reliability
information mirrors what is observed in the experiment.
66 66
Focused Experiment 2b – Reliability Learning Curve
Benefits of reliability info decrease over time as individuals
internalize trip variability
Participants using reliability info perform on week 1 as well as their
counterparts at week 4
67 67
Overall Findings
• Provision of reliability information does improve on-time performance
versus a control group that receives no reliability information
– Simple forms of reliability information had similar results whether provided
in text, graphic or auditory forms
– More complex graphical & signposting concepts not effective
• Benefits of reliability information do decrease over time as participants
build a larger experience base
– The decrease is not as “quick” as expected
– The gap between reliability info users and others does not narrow
• Perceived benefit of reliability information trail actual benefit
– Providers of reliability information may face an uphill battle in measuring
perceptional impacts even when reliability information improves trip
outcomes
Beverly Kuhn, TTI
Lexicon
Lexicon
69
Phrase book to be used across platforms.
Potential uses.
Public outreach.
Performance measure reports.
TMC pre-trip planning websites.
Commercial traffic routing systems.
Lexicon Terminology
70
95th Percentile
Arrival Time
Buffer Time
Departure Time
Recommended Departure Time
Recommended Route
Reliability
Average Travel Time
Lexicon – 95th Percentile
71
Lexicon – Arrival Time
72
72
Lexicon – Buffer Time
73
73
Lexicon – Departure Time
74
74
Lexicon – Recommended Departure Time
75
75
Lexicon – Recommended Route
76
76
Lexicon – Reliability
77
77
Lexicon – Average Travel Time
78
78
Questions
Beverly Kuhn, TTI
979-862-3558
Vaishali Shah, Noblis
202-488-5715
79
Transportation Information Management Program
FHWA-Office of Operations
Jimmy Chu
Disseminating Traveler Information on Travel time Reliability Implementation Plan
• Test Lexicon Terminology developed in L14
• Demonstrate the technical and institutional issues
• Develop a “how-to-guidance”
What is the Initiative?
2/7
• Field tests of Lexicon terminology
• Convey reliability information from theory to reality
• Understand the current and future marketplace
• Understand how travelers use reliability information differently
What are the Objectives?
3/7
• Lay out the barriers to communicating reliability information to travelers and steps to overcome barriers – Users understand the messages
– Users change behavior
– Users trust the information
• Outline steps needed to take getting reliability information into decision processes
4/7
What are the Objectives?
• Conduct tests in three cities – At least one city not providing reliability information currently
– Cities must have data available
– Information on highways only
• Technology Applications – Not on DMS
– 511
– Agencies websites
– Social Media
– Mobile applications.
What are the Objectives?
5/7
• A “ how to “ guidance report
• Three webinars to present the findings
What are the Products?
6/7
Contact Information:
Jimmy Chu Transportation Specialist
[email protected] 202 366 3379
Federal Highway Administration Office of Operations
7/7
Now it’s time for a poll question.
87
Q&A
• Please type your
questions into your
webinar control panel
• We will read your
questions out loud, and
answer as many
questions as time allows.
88
Today’s Panelists and Moderator
• Beverly Kuhn, Texas A&M Transportation Institute [email protected]
• Vaishali Shah, Noblis [email protected]
• Jimmy Chu, Federal Highway Administration [email protected]
• Bill Hyman, Transportation Research Board [email protected]
89
Download Report
• A copy of the final report can be found here:
http://www.trb.org/Main/Blurbs/168809.aspx
• A copy of the lexicon is available at:
http://www.trb.org/Main/Blurbs/168810.aspx
90
Panelist Presentations
• To download the presenters’ slides, go here:
http://onlinepubs.trb.org/onlinepubs/webinars/140
826.pdf
91
