SHRP2 L14
SHRP2 L14 EFFECTIVENESS OF DIFFERENT APPROACHES TO DISSEMINATING TRAVELER INFORMATION ON TRAVEL TIME RELIABILITY
SHRP2 L14 Closeout Meeting – September 26, 2012
Meeting Agenda
Welcome Part 1: Introduction Part 2: Assessment of the Project Part 3: Discussion and Comments on Deliverables Part 4: Next Steps Conclusion
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Part 1: Introduction Beverly Kuhn, TTI
Introductions
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Meeting Objectives
REVIEW context, history, and main outcomes of the SHRP2 L14 project. DISCUSS comments on Guidebook/Lexicon and Final Report. CONCUR on completion timeline, review process for deliverables, publication issues, and implementation.
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Bias / Conflict of Interest Policies
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Part 2: Assessment of the Project Beverly Kuhn, TTI Karl Wunderlich, Noblis
The Elevator Speech This project seeks to develop a lexicon of terms that transportation agencies can use in messages to users concerning the reliability of travel times and facilities in their systems. 8
Context
Uses of reliability information by transportation profession. Mobility
performance measures. Planning and project prioritization. Transit system performance monitoring.
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Context
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.
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L-14 Project Objectives
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. Develop Guidebook and Deployment Advisory. Document research results. 11
Phase 1: Foundational Research
SHRP2 L14: GUIDEBOOK DEVELOPMENT PROCESS
Innovation Scan, State of Practice Report, Expert Interviews
Focus Groups/ Surveys
Precursor Experiment
Phase 2: Focused Experiments
Field Operational Test
Guidebook / 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?
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Phase 1: Foundational Research
SHRP2 L14: CONTRIBUTIONS OF INITIAL FOUNDATIONAL RESEARCH PRODUCTS
Innovation Scan, State of Practice Report, Expert Interviews
Definition of travel time reliability information Current forms and media for reliability information Focus Groups/ Surveys
Precursor Experiment
Phase 2: Focused Experiments
Field Operational Test
Guidebook / 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?
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Phase 1: Foundational Research
SHRP2 L14: CONTIBUTIONS OF SURVEYS AND PRECURSOR EXPERIMENT
Innovation Scan, State of Practice Report, Expert Interviews Definition of travel time reliability information Current forms and media for reliability information Focus Groups/ Surveys Preferred terms Alternative media
Precursor Experiment Evaluation methodology Serenity-sensitive utility function
Phase 2: Focused Experiments
Field Operational Test
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Guidebook / 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?
Phase 1: Foundational Research
SHRP2 L14: CONTIBUTIONS OF SURVEYS AND PRECURSOR EXPERIMENT
Innovation Scan, State of Practice Report, Expert Interviews Definition of travel time reliability information Current forms and media for reliability information Focus Groups/ Surveys Preferred terms Alternative media
Precursor Experiment Evaluation methodology Serenity-sensitive utility function
Phase 2: Focused Experiments
Field Operational Test
• • • • •
• Web interface outside control of research team • Inability to vary information Guidebook / Lexicon displays to test multiple scenarios
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?
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Phase 1: Foundational Research
SHRP2 L14: CONTRIBUTIONS OF EXPANDED EXPERIMENTATION
Innovation Scan, State of Practice Report, Expert Interviews
Definition of travel time reliability information Current forms and media for reliability information Focus Groups/ Surveys Preferred terms Alternative media
Precursor Experiment Evaluation methodology Serenity-sensitive utility function
Phase 2: Focused Experiments
Expanded Experimentation
Guidebook / 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?
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Phase 1: Foundational Research
SHRP2 L14: CONTRIBUTIONS OF EXPANDED EXPERIMENTATION
Innovation Scan, State of Practice Report, Expert Interviews
Definition of travel time reliability information Current forms and media for reliability information Focus Groups/ Surveys Preferred terms Alternative media
Precursor Experiment Evaluation methodology Serenity-sensitive utility function
Phase 2: Focused Experiments
Expanded Experimentation
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Evaluated forms and terms Valuation of reliability info Guidebook / 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?
Phase 1: Foundational Research
SHRP2 L14: RELIABILITY INFORMAITON GUIDEBOOK DEVELOPMENT
Innovation Scan, State of Practice Report, Expert Interviews
Definition of travel time reliability information Current forms and media for reliability information Focus Groups/ Surveys Preferred terms Alternative media
Precursor Experiment Evaluation methodology Serenity-sensitive utility function
Phase 2: Focused Experiments
Expanded Experimentation Evaluated forms and terms Valuation of reliability info Guidebook / 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?
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Reliability Information
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.
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Examples of Reliability Information as communicated “person-to-person”
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 5050 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.
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Interplay between Reliability and RealTime Information in Decision Making HOW LONG SHOULD I EXPECT THIS TRIP TO TAKE? RELIABILITY INFORMATION
REAL-TIME INFO/CUEING
Great Day: 35 min Good Day: 40 min Bad Day: 75 min *XDOT 6mo archive
The last traffic report didn’t mention the freeway I use MY EXPERIENCE My last trip was about an hour
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Reliability Information has Highest Influence When Trip Experience is Low 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 (strong)
REAL-TIME INFO/CUEING
What radio station carries traffic information? (weak)
MY EXPERIENCE I have never taken this trip before
(weak)
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Phase 1: Foundational Research Beverly Kuhn (TTI)
Literature Review Beverly Kuhn (TTI)
Literature Review
Travel time reliability metrics. Importance of travel time reliability for highway travel, transit, and freight. State of the practice. Real-time
travel information. Language used by lay people to talk about range, standard deviation, confidence intervals.
Language from other fields. 25
Washington State DOT
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San Francisco Bay 511.org
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FlightStats.com
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Expert Interviews Beverly Kuhn (TTI)
Interview Topics
Current methods and experiences related to use of travel reliability information.
Value of reliability information.
State DOTs. Private sector. The public. Transportation operations staff Public officials.
Potential impacts, goals, challenges. Little dissemination of reliability information currently. 30
Key Findings
Value to the public. Believe
has value to the public. Gives an idea of “riskiness”.
Value to operations staff and public officials. Used
to assess performance of the system. Help determine where improvements are needed. Used to manage networks and justify programs to improve performance. Help understand the impact of non-recurring congestion on system performance. 31
Potential Impacts
Highly dependent upon whether or not the public understands the information provided. Information accuracy important. Dependent upon the actual number of travelers who will use the information for trip planning.
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Inrix Traffic!
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Challenges to Dissemination
Inability to quickly collect and analyze data. Limited staffing. Determining a format that will be accepted and understood by users. Need for quality data. Implementations in multi-jurisdictional areas.
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Short and Long-term Goals
Most agencies beginning to discuss the idea of providing reliability information to the public. Potential media. Internet. 511 systems. Mobile phone applications.
Agencies already providing information. Improve data quality. Expand coverage. Provide customizable reports and statistics. Provide new media options.
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Technology and Innovation Scan Beverly Kuhn (TTI)
Technology and Innovation Scan
Innovations in the marketplace. In-vehicle
systems changing and expanding. Safety implications.
Market forces. Crowdsourcing,
web-based
innovations. Consolidation and integration.
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Better Data to Come
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Innovative Media
Navigon 5100 3.5-Inch Portable GPS Navigator with Text-to-Speech and Lifetime Traffic
Magellan Maestro 4050 4.3-Inch Widescreen Bluetooth Portable GPS Navigator
Garmin nüvi 650 4.3Inch Widescreen Portable GPS Navigator
TomTom GO 920 Portable GPS Vehicle Navigator
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Develop Avenues of Investigation Beverly Kuhn (TTI)
Develop Avenues of Investigation
Assessment of results. Literature
review. Expert interviews. Technology scan.
Identified key research issues. Direct the remaining activities.
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Key Research Issues
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? 42
Key Research Issues
Do travelers want this info pre-trip or en route? Does their desire for info change as function of trip purpose, route, constraints? Can travelers safely use an en route in-vehicle system? 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? 43
Key Research Issues
Do travelers want this info pre-trip or en route? Does their desire for info change as function of trip purpose, route, constraints? Can travelers safely use an en route in-vehicle system? 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? 44
Focus Groups Beverly Kuhn (TTI)
Focus Groups – Purpose
Assess understanding of reliability concepts. Identify terms / determine desire for travel time reliability information. Assess desired system features. Assess willingness to pay. 116 people. Seattle, Minneapolis, Atlanta, Houston, Washington DC. 46
Focus Groups – Script Development
Initial scripts contained more analog cases to elicit discussion of reliability concepts. E.g. Online Order Shipping Time. Initial scripts contained more examples of web graphs. Much confusion among reliability and real-time systems.
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Examples of Graphics Used in Initial Focus Groups to Elicit Reliability Terms
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Example Web Graphic Used in Initial Focus Groups
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Final Focus Group Discussion Guide Topics Constrained Arrival Time Unfamiliar Destination
Appointment with new doctor
Familiar Destination
Regular commute
Task Insertion
Constrained Departure Time
Unconstrained Weekend evening party Weekend getaway 3 hours away
Choosing Day of the Week for Class After Work
Pick up produce from farm co-op anytime Saturday Stop by neighbors to feed cat
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Focus Groups – Findings
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. 51
How Focus Group Results Affected Subsequent Work
Inclusion of additional questions to elicit more lexicon terms. Addition of open-ended survey. Addition of Noblis precursor experiment. Reduced emphasis on graphical displays.
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Usability Testing, Survey, Experiment Beverly Kuhn (TTI) Karl Wunderlich (Noblis)
Scope & Purpose
Determine comprehension and preference of reliability terms. Elicit additional terms for Lexicon. Test user acceptance of reliability terms. Determine information use, serenity benefits, willingness to pay, swiftness of personal historical framework.
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Computer Survey Beverly Kuhn (TTI)
Computer Survey – Purpose
More multiple choice questions on concepts and terms. Preference for departure or arrival time input. Hypothetical website
Term preferences
Input Output Screen titles and labels
N=300: San Jose, Dallas, Hartford, Denver, Miami. Sites selected based on mobility report rankings, presence of transit and HOV/HOT lanes. 56
Survey Website
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Key Findings
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.). 58
Open-ended Survey Beverly Kuhn (TTI)
Open-ended Questions
Comprehension of reliability and associated terms. Preference of terms and reliability information. Presented trip planning situations for an arrival timeconstrained motorist that included either. The
normal trip time and an uncertainty component. The normal trip time and the overall trip time to plan for.
Normal Trip Time + Uncertainty of Conditions During Trip = Trip Time to Plan For 60
Open-ended Survey
Open-ended Survey Terms Normal Trip Time
Uncertainty Component
Trip Time to Plan for
Average Travel Time
Added Time
95th Percentile Travel Time
Expected Travel Time
Extra Time
Travel Time for Planning
Typical Travel Time
Cushion Time
Most of the Time Less Than
Estimated Travel Time
Recommended Cushion Time
Majority of the Time Less Than
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Open-ended Survey
Testing conducted in January in Hartford, San Jose, and Dallas. N = 190 Manual data entry and scoring required.
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Key Findings
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. 64
Key Findings
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. 65
Precursor Experiment – Utility Function Karl Wunderlich (Noblis)
Precursor Experiment Hypotheses 1. Provision of accurate reliability information will result in improved on-time performance and lower generalized travel disutility 2. The perceived value of the reliability information will lag realized benefit. 3. Benefits of reliability information will decline as subjects become familiar with travel time variability 4. There is a “serenity benefit” to traveler information 67
Precursor Experiment Parameters
80 participants in 5 cities Conducted in conjunction with computer surveys 3 levels of additive information: DMS, real-time, reliability Each participant uses one level of traveler information throughout experiment 10 commute days, each with 3 departure times Two decision points for route diversion Report completed Sep 2011 68
SCREEN SHOT OF PRECURSOR EXPERIMENT RELIABILITY, REAL-TIME, AND DMS INFORMATION
Experiment Outcomes Participants with reliability information on average left earlier more often than those without it.
Implication: Reliability information does influence departure time decisions.
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Findings – Hypothesis #1 Provision of reliability info results in on-time performance improvement, and lower generalized travel disutility
*schedule offset costs defined within the experiment
Implication: Reliability information quantitatively benefits unfamiliar time-constrained travelers 71
Findings – Hypothesis #2 Perceptions of benefit as measured through value of information and trip stress do not differ statistically by level of information whereas trip outcomes do. Implication: Providers of reliability information may face an uphill battle in measuring perceptional impacts of reliability information impacts even when such information is useful in improving trip outcomes.
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Findings – Hypothesis #3 & #4
Decline in reliability information benefits not observed while participants’ willingness to pay for reliability information declined over time Traveler do place a value on knowing they will be late even if the trip outcome cannot be changed.
Implication-It may be that 2 weeks is insufficient for travelers without reliability information to internalize trip variability and perform at par with counterparts 73
Phase 2: Focused Experiment Karl Wunderlich (Noblis) Vaishali Shah (Noblis)
Experiment Hypotheses 1. Provision of reliability information improves ontime performance versus a control group that receives no reliability information a. Some forms will be more effective than others b. Perceived benefit will trail actual benefit 2. The provision of reliability signposts in real-time information will improve on-time performance 3. Benefits of reliability information will decrease over time as participants build a larger experience base
Expanded Experiment Changes…
Only qualitative real-time info provided, previously quantitative & qualitative real-time info provided Seven rather than 3 departure options Eliminate alternate route option Seven ‘types’ of reliability info instead of one 4-5 weeks instead of 2 weeks of simulated commute 240 participants rather than 80 participants Two distinct sets of experiments 76
Two Distinct Experiments
Experiment #1 –Compare different forms and content of data to unfamiliar travelers
5 sets of reliability information tested by each participant through 5 weeks of simulated commuting, each week in a different city.
Experiment #2 – Compare the learning curve for unfamiliar travelers with or without reliability information Half of participants receive simulated reliability information over a 4 week period in one city Other half do not receive any reliability information.
Experiment #1: Test 7 Reliability Terms (based on terminology document)
F.
Baseline radio information presented textually Text-based 95th percentile Text-based average plus 95th percentile Text-based 20th, average, and 95th percentile Reliability Signposting Graphical “C” G. Graphical “D”
H.
Auditory “B”
A. B. C. D. E.
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Experiment Implementation
Pre-experiment survey, commuting game, and mini post-experiment survey for Exp#1 users Often experiment completed within 60-70 minutes in Washington DC, while we ‘had’ participants for 90 minutes. Consequently, paper survey added in Chicago and Houston requests participants rank six of seven types of info (auditory was excluded)
Expanded Experiment Design
Reliability Data Content
#1 Two Distinct Experiments: 5 cities, 1 week each city* Implementation Version Planned Participant Count Valid "good" Participant Count A. Control (no reliability info) B. C. D. E. F. G. H.
Textual 95TH Textual Avg + 95TH Textual 20TH+ Avg + 95TH Visual and Textual signposting Graphical presentation of "C" Graphical presentation of "D" Auditory presentation of "B"
1 90 98 P P P P P
2 30 29 P P P P P
3 30 25 P P P
#2 1 city*, 4 wks.
4 30 33 P
5 30 30 P
6 30 30
P P
P P
P P
P
*city refers to travel in simulated city for participants and not city of experiment implementation
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Participant Characteristics
More educated sample than population at large Older sample population than population at large Definition of Late Arrival
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Exp#1 Schedule Offset Costs
Schedule offset savings are statistically and practically significant for simpler forms of reliability information
*lighter shades are not statistically significant
No Reliability Info Reliability Info 82
Exp#1 Late Arrival Frequency
When offered simpler forms of reliability information, participants were late less often
*lighter shades are not statistically significant
No Reliability Info Reliability Info 83
Exp#1 Perceived Benefits
End-of-week difference in willingness to pay often not statistically significant between trips with and without reliability information End-of-week usefulness higher for ‘simple’ reliability information but not for ‘complex’ reliability data. Post-trip usefulness and stressfulness levels often not statistically significant or lower for reliability terms
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Exp#1 Comparing Delivery Media
Text v. Auditory 95th Percentile Info Generally
no statistically significant differences for trip outcomes or valuation Text rated slightly more difficult to understand compard 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 85
Exp#1 Comparing Delivery Media
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.
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Exp#2 Late Arrival Frequency
Benefits of reliability info decrease over time Participants using reliability info perform on week 1 as well as their counterparts at week 4
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Exp#1 Post Survey Survey replies on reliability info usefulness and complexity mirrors what is observed in the experiment. Benefits reflects difference between usefulness and complexity. 88
Paper Post-Experiment Survey Different ratings from paper survey on the usefulness of reliability information compared to the quantified valuation observed in the first experiment. Complex graphic rated equivalent to text 95th with regard to usefulness. 89
Findings – Hypothesis #1 1. Provision of reliability information does improves ontime performance versus a control group that receives no reliability information a. Some forms are more effective than others Provision of simple forms of reliability information had similar results whether provided in text, graphic or auditory forms. More complex graphical & signposting concepts not effective. b. Perceived benefit do trail actual benefit Perceived benefits unclear in presence of quantitative benefits.
Findings – Hypothesis #2 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.
Findings – Hypothesis #3
The provision of reliability signposts in real-time information does not improve on-time performance The
signposting concept was not successful for participants in the management of trip outcomes and stress reduction. To some degree, this was because of the complexity of the presentation and the brevity with which participants were required to learn and interpret information content.
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Potential Future Research Directions
Reliability information in the context of more complex multi-modal trip, trip chain and tour planning. Impact of reliability information on broader range of travel-related choices. Mechanisms of reliability information under-valuation by users.
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Part 3: Discussion and Comments on Deliverables Beverly Kuhn, TTI
Lexicon
Phrase book to be used across platforms. Potential uses. Public
outreach. Performance measure reports. TMC pre-trip planning websites. Commercial traffic routing systems.
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Guidebook Chapters
1 – Introduction 2 – The Concept of Travel Time Reliability 3 – Key Messages 4 – Relevant Travel Time Reliability Terms 5 – Methods of Communicating Travel Time Reliability 6 – Measuring Information Effectiveness 7 – Emerging Trends 8 – Final Remarks 9 – References 96
Lexicon Terminology
95th Percentile Arrival Time Average Travel Time Buffer Time Departure Time Recommended Departure Time Recommended Route Reliability 97
Lexicon –
th 95
Percentile
Technical Term 95th Percentile Definition The point on a travel time frequency distribution at which 95% of the trips made would be at or less than the identified time. Usage To describe the longest time a driver can expect a trip to take. Information Technology Platforms Recommendation
Alternate Phrase
Majority of the time Best
Wording Context / Additional Information “The majority of the time, your trip will take X minutes or less.” MAJORITY OF TIME TRIP TO [DESTINATION] X MIN OR LESS Graphical representation of the average + 95th percentile.
Most of the time
Adequate Travel time for planning
95th percentile trip time
Avoid
Maximum trip time Most common trip time Worst case trip time
“Most of the time, your trip will take X minutes or less.” MOST OF THE TIME TRIP TO [DESTINATION] X MIN OR LESS “Travel time for planning is X minutes or less.” “The 95th percentile trip time is X minutes or less.” Provide description such as “19 out of 20 days”. Agency concerns regarding liability and credibility.
Web
Mobile Web
Dynamic Message Sign
Text
Mobile Application
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98N/A
Lexicon – Arrival Time Technical Term Definition Usage
Arrival Time The time at which a traveler would arrive after a trip. To tell the driver when they can expect to arrive at their destination.
99 Recommendation
Best
Alternate Phrase
Arrive by Arrive at
What time do you want to get there?
Adequate
What’s the earliest you can arrive
What’s the latest you can arrive?
Wording Context / Additional Information “Arrive by X:XX am / pm.” ARRIVE BY X:XX AM/PM “Arrive at X:XX am / pm.” ARRIVE AT X:XX AM/PM This question would be used by a traveler to enter a preferred arrival time into a travel time calculator to receive a recommended departure time. This question would be used by a traveler to enter a preferred arrival time into a travel time calculator to receive a recommended departure time. This question would be used by a traveler to enter a preferred arrival time into a travel time calculator to receive a recommended departure time.
Information Technology Platforms Dynam Mobile Mobile ic Applica Web Text Messag Web tion e Sign √ √ X √ √ √ √ √>% √ √ √ √ X √ √ √ √ √>% √ √
√
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Avoid
99
10 0
Lexicon – Average Travel Time Technical Term Average Travel Time Definition An average of historical travel times calculated over a specified time interval for a specified trip or roadway segment. Usage To describe the typical travel time a driver can expect a trip will take. Information Technology Platforms Recommendation
Alternate Phrase
Wording Context / Additional Information
Web
Mobile Web
Dynamic Message Sign
Text
Mobile Application
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X
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“Typical travel time is X minutes.”
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Graphical representation of the average + 95th percentile (typical day and bad day).
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X
X
√
Graphical representation of the 20th percentile + average + 95th percentile (good, typical, and bad day).
√
√
X
X
√
“Average travel time is X minutes.”
√
√
X
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“Expected travel time is X minutes.”
√
√
X
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Difficult to determine relevance with no comparison to real-time information.
N/A
N/A
N/A
N/A
“Estimated travel time is X minutes.” Estimated travel time Best
Approximate travel time Typical travel time
Adequate
Average travel time Expected travel time
Avoid
Historical Travel Time
“It is estimated that your trip will take X minutes.” EST THAT TRIP TO [DESTINATION] WILL TAKE X MIN “It will take approximately X minutes to make your trip.” APPROX X MIN TO [DESTINATION]
100 N/A
10 1
Lexicon – Buffer Time Technical Term Definition Usage
Buffer Time The average travel time multiplied by the buffer index. To describe how much extra time a driver should plan for a trip they wish to take. Information Technology Platforms
Recommendation
Alternate Phrase
Best
Extra time
Web
Mobile Web
Dynamic Message Sign
Text
Mobile Application
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X
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X
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“Recommended cushion for trip is X minutes.”
√
√
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Preference shown for other terms.
N/A
N/A
N/A
N/A
N/A
Wording Context / Additional Information
“Extra time for trip is X minutes.” Extra time to [destination] is X min “Added time for trip is X minutes.”
Added time Adequate
Avoid
Recommended cushion Cushion
Added time to [destination] is X min
101
10 2
Lexicon – Departure Time Technical Term Departure Time Definition The time at which a traveler would depart for a trip. Usage To indicate the time a traveler departs for a trip. For DMS applications, message would need to be set in context with other information, such as destination, travel time, or route.
Recommendation
Best
Adequate
Alternate Phrase Departing at Leave at What time will you start your trip?
Leave by Departing by What’s the earliest you can start your trip?
What’s the latest you can start your trip?
Wording Context / Additional Information “Departing at X:XX am / pm.” “Leave at X:XX am / pm.” This question would be used by a traveler to enter a start time into a travel time calculator to receive an arrival time. “Leave by X:XX am / pm.” “Departing by X:XX am / pm.” This question would be used by a traveler to enter a start time into a travel time calculator to receive an arrival time. This question would be used by a traveler to enter a start time into a travel time calculator to receive an arrival time.
Web √ √
Information Technology Platforms Dynamic Mobile Mobile Message Text Web Application Sign √ X √ √ √ X √ √
√
√
X
X
√
√ √
√ √
X X
√ √
√ √
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X
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X
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Avoid
102
10 3
Lexicon – Recommended Departure Time Technical Term Recommended Departure Time Definition A time of departure displayed to a traveler which is calculated by a traveler information system and would ensure an ontime arrival for a given level of added delay. Usage To indicate the time a driver should depart for a trip to ensure they arrive at their destination on time. For DMS applications, would need to be set in context with other information, such as destination, travel time, or route.
Recommendation
Best
Adequate
Alternate Phrase
Wording Context / Additional Information
Recommended departure “Recommended departure time is time X:XX am / pm.” Suggested departure time “Suggested departure time is X:XX am / pm.” Estimated departure “Estimated departure time is X:XX time> am / pm.” >> “The 95th percentile departure th 95 percentile departure time is X:XX am / pm.” Provide description such as “19 time out of 20 days”.
Web
Information Technology Platforms Dynamic Mobile Mobile Message Text Web Application Sign
√
√
X
√+
√+
√
√
X
√+
√+
√
√
X
√+
√+
√
√
X
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√+
Avoid
103
10 4
Lexicon – Recommended Route Technical Term Recommended Route Definition A route between two points calculated by a traveler information system which would provide the best probability of on-time arrival to a specific destination. Usage To describe the route a driver should take for a planned trip to ensure he/she arrives on time to his/her destination.
Recommendation
Best
Alternate Phrase
Best route Forecasted trip
Most reliable trip
Adequate
Most predictable trip
Most consistent trip
Wording Context / Additional Information
√
√
X
√+
√+
√
√
√>
√
√
√
√
X
√+
√+
√
√
√>
√
√
√
√
X
√+
√+
√
√
√>
√
√
√
√
X
√+
√+
MOST PREDICTABLE TRAVEL TIME TO [DESTINATION] TAKE [FACILITY]
√
√
√>
√
√
“Most consistent trip is via [facility].”
√
√
X
√+
√+
√
√
√>
√
√
N/A
N/A
N/A
N/A
“Best route is via [facility].” BEST ROUTE TO [DESTINATION] TAKE [FACILITY] “Forecasted trip is via [facility].” FORECASTED TRIP TIME VIA [FACILITY] X MIN “Most reliable trip is via [facility].” MOST RELIABLE TRAVEL TIME TO [DESTINATION] TAKE [FACILITY] “Most predictable trip is via [facility].”
MOST CONSISTENT TRAVEL TIME TO [DESTINATION] TAKE [FACILITY]
Avoid
Historical trip conditions Least variable time
Web
Information Technology Platforms Dynamic Mobile Mobile Message Text Web Application Sign
Difficult to determine relevance with no comparison to real-time information. Preference shown for other terms.
104 N/A
10 5
Lexicon – Reliability Technical Term Reliability Definition A consistency or dependability in travel times between two points, as measured from day to day or across different times of day. Usage To describe the variability of travel times to drivers so they can plan their trip with more robust information.
Recommendation
Alternate Phrase
Best
Predictable Reliable Consistent Vary Differ Fluctuate Change Go up or down Increase or decrease Deviate
Adequate
Avoid
Wording Context / Additional Information
Web
“Most predictable trip” “Most reliable trip.” “Most consistent trip.” “Trip varies.”
√ √ √ √
Preference shown for other terms.
N/A
Information Technology Platforms Dynamic Mobile Mobile Message Text Web Application Sign √ X √ √ √ X √ √ √ X √ √ √ X √ √
N/A
N/A
N/A
N/A
105
Lexicon Not Provided
Buffer Index Not tested in the human factors studies. Metric unlikely to be used by roadway users.
Delay Time Not tested in human factors studies. Terms tested for the related concept “buffer time”.
Free Flow Travel Time Not tested in focus groups or surveys. Phrase “great day” used in enhanced laboratory study along with corresponding “typical” and “bad” days.
106
Lexicon Not Provided
Peak Travel Time Not tested in the human factors studies. Terms tested for similar concept “95th percentile travel time”.
Planning Time Not tested in the human factors studies. Terms tested for similar concept “95th percentile travel time”. “Travel time for planning” was one of the alternatives tested to represent 95th percentile travel time.
Planning Time Index Not tested in the human factors studies. Metric unlikely to be used by roadway users.
107
Lexicon Not Provided
Total Trip Time Not tested in human factors studies. A commonly-used phrase and few synonyms exist.
Travel Time Savings Not tested in human factors studies. A commonly-used phrase and few synonyms exist.
Travel Time Range
In computer survey, subjects more often felt a single trip time (typical/avg or 95th percentile) was reliable when compared to a travel time range.
Trend Information
Not tested in human factors studies. 108
Final Report
1 – Introduction 2 – Literature Review 3 – Expert Interviews 4 – Technology and Innovation Scan 5 – Develop Avenues of Investigation 6 – Focus Groups 7 – Usability Surveys
8 – Travel Behavior Laboratory Experiment 9 – Enhanced Laboratory Experiment 10 – Lexicon Development 11 – Final Remarks 12 – References
109
Part 4: Next Steps Beverly Kuhn, TTI Karl Wunderlich, Noblis
Project Timeline
Project Closeout Meeting with TETG
Sep 26, 2012
Discuss comments on Draft Guidebook & Deployment Advisory
Discuss comments on Final Report
Address TETG Comments & Submit Final Documents
Draft Guidebook & Deployment Advisory
Final Report
Oct 15, 2012
Review Process
Oct-Jan 2013
Project Conclusion
Jan 31, 2013
111
Product Review Process
112
Publication Issues
113
Implementation
How can the main outcome of this project – the Guidebook and Deployment Advisory – be used by an operating agency? Who are the potential first users?
114
Questions Beverly Kuhn, TTI [email protected] 979-862-3558 Karl Wunderlich, Noblis [email protected] 202-488-5707 Vaishali Shah, Noblis [email protected] 202-488-5715 115
SHRP2 L14 Closeout Meeting – September 26, 2012
Meeting Agenda
Welcome Part 1: Introduction Part 2: Assessment of the Project Part 3: Discussion and Comments on Deliverables Part 4: Next Steps Conclusion
2
Part 1: Introduction Beverly Kuhn, TTI
Introductions
4
Meeting Objectives
REVIEW context, history, and main outcomes of the SHRP2 L14 project. DISCUSS comments on Guidebook/Lexicon and Final Report. CONCUR on completion timeline, review process for deliverables, publication issues, and implementation.
5
Bias / Conflict of Interest Policies
6
Part 2: Assessment of the Project Beverly Kuhn, TTI Karl Wunderlich, Noblis
The Elevator Speech This project seeks to develop a lexicon of terms that transportation agencies can use in messages to users concerning the reliability of travel times and facilities in their systems. 8
Context
Uses of reliability information by transportation profession. Mobility
performance measures. Planning and project prioritization. Transit system performance monitoring.
9
Context
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.
10
L-14 Project Objectives
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. Develop Guidebook and Deployment Advisory. Document research results. 11
Phase 1: Foundational Research
SHRP2 L14: GUIDEBOOK DEVELOPMENT PROCESS
Innovation Scan, State of Practice Report, Expert Interviews
Focus Groups/ Surveys
Precursor Experiment
Phase 2: Focused Experiments
Field Operational Test
Guidebook / 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?
5
Phase 1: Foundational Research
SHRP2 L14: CONTRIBUTIONS OF INITIAL FOUNDATIONAL RESEARCH PRODUCTS
Innovation Scan, State of Practice Report, Expert Interviews
Definition of travel time reliability information Current forms and media for reliability information Focus Groups/ Surveys
Precursor Experiment
Phase 2: Focused Experiments
Field Operational Test
Guidebook / 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?
6
Phase 1: Foundational Research
SHRP2 L14: CONTIBUTIONS OF SURVEYS AND PRECURSOR EXPERIMENT
Innovation Scan, State of Practice Report, Expert Interviews Definition of travel time reliability information Current forms and media for reliability information Focus Groups/ Surveys Preferred terms Alternative media
Precursor Experiment Evaluation methodology Serenity-sensitive utility function
Phase 2: Focused Experiments
Field Operational Test
7
Guidebook / 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?
Phase 1: Foundational Research
SHRP2 L14: CONTIBUTIONS OF SURVEYS AND PRECURSOR EXPERIMENT
Innovation Scan, State of Practice Report, Expert Interviews Definition of travel time reliability information Current forms and media for reliability information Focus Groups/ Surveys Preferred terms Alternative media
Precursor Experiment Evaluation methodology Serenity-sensitive utility function
Phase 2: Focused Experiments
Field Operational Test
• • • • •
• Web interface outside control of research team • Inability to vary information Guidebook / Lexicon displays to test multiple scenarios
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?
7
Phase 1: Foundational Research
SHRP2 L14: CONTRIBUTIONS OF EXPANDED EXPERIMENTATION
Innovation Scan, State of Practice Report, Expert Interviews
Definition of travel time reliability information Current forms and media for reliability information Focus Groups/ Surveys Preferred terms Alternative media
Precursor Experiment Evaluation methodology Serenity-sensitive utility function
Phase 2: Focused Experiments
Expanded Experimentation
Guidebook / 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?
8
Phase 1: Foundational Research
SHRP2 L14: CONTRIBUTIONS OF EXPANDED EXPERIMENTATION
Innovation Scan, State of Practice Report, Expert Interviews
Definition of travel time reliability information Current forms and media for reliability information Focus Groups/ Surveys Preferred terms Alternative media
Precursor Experiment Evaluation methodology Serenity-sensitive utility function
Phase 2: Focused Experiments
Expanded Experimentation
8
Evaluated forms and terms Valuation of reliability info Guidebook / 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?
Phase 1: Foundational Research
SHRP2 L14: RELIABILITY INFORMAITON GUIDEBOOK DEVELOPMENT
Innovation Scan, State of Practice Report, Expert Interviews
Definition of travel time reliability information Current forms and media for reliability information Focus Groups/ Surveys Preferred terms Alternative media
Precursor Experiment Evaluation methodology Serenity-sensitive utility function
Phase 2: Focused Experiments
Expanded Experimentation Evaluated forms and terms Valuation of reliability info Guidebook / 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?
9
Reliability Information
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.
19
Examples of Reliability Information as communicated “person-to-person”
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 5050 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.
20
Interplay between Reliability and RealTime Information in Decision Making HOW LONG SHOULD I EXPECT THIS TRIP TO TAKE? RELIABILITY INFORMATION
REAL-TIME INFO/CUEING
Great Day: 35 min Good Day: 40 min Bad Day: 75 min *XDOT 6mo archive
The last traffic report didn’t mention the freeway I use MY EXPERIENCE My last trip was about an hour
21
Reliability Information has Highest Influence When Trip Experience is Low 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 (strong)
REAL-TIME INFO/CUEING
What radio station carries traffic information? (weak)
MY EXPERIENCE I have never taken this trip before
(weak)
22
Phase 1: Foundational Research Beverly Kuhn (TTI)
Literature Review Beverly Kuhn (TTI)
Literature Review
Travel time reliability metrics. Importance of travel time reliability for highway travel, transit, and freight. State of the practice. Real-time
travel information. Language used by lay people to talk about range, standard deviation, confidence intervals.
Language from other fields. 25
Washington State DOT
26
San Francisco Bay 511.org
27
FlightStats.com
28
Expert Interviews Beverly Kuhn (TTI)
Interview Topics
Current methods and experiences related to use of travel reliability information.
Value of reliability information.
State DOTs. Private sector. The public. Transportation operations staff Public officials.
Potential impacts, goals, challenges. Little dissemination of reliability information currently. 30
Key Findings
Value to the public. Believe
has value to the public. Gives an idea of “riskiness”.
Value to operations staff and public officials. Used
to assess performance of the system. Help determine where improvements are needed. Used to manage networks and justify programs to improve performance. Help understand the impact of non-recurring congestion on system performance. 31
Potential Impacts
Highly dependent upon whether or not the public understands the information provided. Information accuracy important. Dependent upon the actual number of travelers who will use the information for trip planning.
32
Inrix Traffic!
33
Challenges to Dissemination
Inability to quickly collect and analyze data. Limited staffing. Determining a format that will be accepted and understood by users. Need for quality data. Implementations in multi-jurisdictional areas.
34
Short and Long-term Goals
Most agencies beginning to discuss the idea of providing reliability information to the public. Potential media. Internet. 511 systems. Mobile phone applications.
Agencies already providing information. Improve data quality. Expand coverage. Provide customizable reports and statistics. Provide new media options.
35
Technology and Innovation Scan Beverly Kuhn (TTI)
Technology and Innovation Scan
Innovations in the marketplace. In-vehicle
systems changing and expanding. Safety implications.
Market forces. Crowdsourcing,
web-based
innovations. Consolidation and integration.
37
Better Data to Come
38
Innovative Media
Navigon 5100 3.5-Inch Portable GPS Navigator with Text-to-Speech and Lifetime Traffic
Magellan Maestro 4050 4.3-Inch Widescreen Bluetooth Portable GPS Navigator
Garmin nüvi 650 4.3Inch Widescreen Portable GPS Navigator
TomTom GO 920 Portable GPS Vehicle Navigator
39
Develop Avenues of Investigation Beverly Kuhn (TTI)
Develop Avenues of Investigation
Assessment of results. Literature
review. Expert interviews. Technology scan.
Identified key research issues. Direct the remaining activities.
41
Key Research Issues
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? 42
Key Research Issues
Do travelers want this info pre-trip or en route? Does their desire for info change as function of trip purpose, route, constraints? Can travelers safely use an en route in-vehicle system? 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? 43
Key Research Issues
Do travelers want this info pre-trip or en route? Does their desire for info change as function of trip purpose, route, constraints? Can travelers safely use an en route in-vehicle system? 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? 44
Focus Groups Beverly Kuhn (TTI)
Focus Groups – Purpose
Assess understanding of reliability concepts. Identify terms / determine desire for travel time reliability information. Assess desired system features. Assess willingness to pay. 116 people. Seattle, Minneapolis, Atlanta, Houston, Washington DC. 46
Focus Groups – Script Development
Initial scripts contained more analog cases to elicit discussion of reliability concepts. E.g. Online Order Shipping Time. Initial scripts contained more examples of web graphs. Much confusion among reliability and real-time systems.
47
Examples of Graphics Used in Initial Focus Groups to Elicit Reliability Terms
48
Example Web Graphic Used in Initial Focus Groups
49
Final Focus Group Discussion Guide Topics Constrained Arrival Time Unfamiliar Destination
Appointment with new doctor
Familiar Destination
Regular commute
Task Insertion
Constrained Departure Time
Unconstrained Weekend evening party Weekend getaway 3 hours away
Choosing Day of the Week for Class After Work
Pick up produce from farm co-op anytime Saturday Stop by neighbors to feed cat
50
Focus Groups – Findings
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. 51
How Focus Group Results Affected Subsequent Work
Inclusion of additional questions to elicit more lexicon terms. Addition of open-ended survey. Addition of Noblis precursor experiment. Reduced emphasis on graphical displays.
52
Usability Testing, Survey, Experiment Beverly Kuhn (TTI) Karl Wunderlich (Noblis)
Scope & Purpose
Determine comprehension and preference of reliability terms. Elicit additional terms for Lexicon. Test user acceptance of reliability terms. Determine information use, serenity benefits, willingness to pay, swiftness of personal historical framework.
54
Computer Survey Beverly Kuhn (TTI)
Computer Survey – Purpose
More multiple choice questions on concepts and terms. Preference for departure or arrival time input. Hypothetical website
Term preferences
Input Output Screen titles and labels
N=300: San Jose, Dallas, Hartford, Denver, Miami. Sites selected based on mobility report rankings, presence of transit and HOV/HOT lanes. 56
Survey Website
57
Key Findings
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.). 58
Open-ended Survey Beverly Kuhn (TTI)
Open-ended Questions
Comprehension of reliability and associated terms. Preference of terms and reliability information. Presented trip planning situations for an arrival timeconstrained motorist that included either. The
normal trip time and an uncertainty component. The normal trip time and the overall trip time to plan for.
Normal Trip Time + Uncertainty of Conditions During Trip = Trip Time to Plan For 60
Open-ended Survey
Open-ended Survey Terms Normal Trip Time
Uncertainty Component
Trip Time to Plan for
Average Travel Time
Added Time
95th Percentile Travel Time
Expected Travel Time
Extra Time
Travel Time for Planning
Typical Travel Time
Cushion Time
Most of the Time Less Than
Estimated Travel Time
Recommended Cushion Time
Majority of the Time Less Than
62
Open-ended Survey
Testing conducted in January in Hartford, San Jose, and Dallas. N = 190 Manual data entry and scoring required.
63
Key Findings
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. 64
Key Findings
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. 65
Precursor Experiment – Utility Function Karl Wunderlich (Noblis)
Precursor Experiment Hypotheses 1. Provision of accurate reliability information will result in improved on-time performance and lower generalized travel disutility 2. The perceived value of the reliability information will lag realized benefit. 3. Benefits of reliability information will decline as subjects become familiar with travel time variability 4. There is a “serenity benefit” to traveler information 67
Precursor Experiment Parameters
80 participants in 5 cities Conducted in conjunction with computer surveys 3 levels of additive information: DMS, real-time, reliability Each participant uses one level of traveler information throughout experiment 10 commute days, each with 3 departure times Two decision points for route diversion Report completed Sep 2011 68
SCREEN SHOT OF PRECURSOR EXPERIMENT RELIABILITY, REAL-TIME, AND DMS INFORMATION
Experiment Outcomes Participants with reliability information on average left earlier more often than those without it.
Implication: Reliability information does influence departure time decisions.
70
Findings – Hypothesis #1 Provision of reliability info results in on-time performance improvement, and lower generalized travel disutility
*schedule offset costs defined within the experiment
Implication: Reliability information quantitatively benefits unfamiliar time-constrained travelers 71
Findings – Hypothesis #2 Perceptions of benefit as measured through value of information and trip stress do not differ statistically by level of information whereas trip outcomes do. Implication: Providers of reliability information may face an uphill battle in measuring perceptional impacts of reliability information impacts even when such information is useful in improving trip outcomes.
72
Findings – Hypothesis #3 & #4
Decline in reliability information benefits not observed while participants’ willingness to pay for reliability information declined over time Traveler do place a value on knowing they will be late even if the trip outcome cannot be changed.
Implication-It may be that 2 weeks is insufficient for travelers without reliability information to internalize trip variability and perform at par with counterparts 73
Phase 2: Focused Experiment Karl Wunderlich (Noblis) Vaishali Shah (Noblis)
Experiment Hypotheses 1. Provision of reliability information improves ontime performance versus a control group that receives no reliability information a. Some forms will be more effective than others b. Perceived benefit will trail actual benefit 2. The provision of reliability signposts in real-time information will improve on-time performance 3. Benefits of reliability information will decrease over time as participants build a larger experience base
Expanded Experiment Changes…
Only qualitative real-time info provided, previously quantitative & qualitative real-time info provided Seven rather than 3 departure options Eliminate alternate route option Seven ‘types’ of reliability info instead of one 4-5 weeks instead of 2 weeks of simulated commute 240 participants rather than 80 participants Two distinct sets of experiments 76
Two Distinct Experiments
Experiment #1 –Compare different forms and content of data to unfamiliar travelers
5 sets of reliability information tested by each participant through 5 weeks of simulated commuting, each week in a different city.
Experiment #2 – Compare the learning curve for unfamiliar travelers with or without reliability information Half of participants receive simulated reliability information over a 4 week period in one city Other half do not receive any reliability information.
Experiment #1: Test 7 Reliability Terms (based on terminology document)
F.
Baseline radio information presented textually Text-based 95th percentile Text-based average plus 95th percentile Text-based 20th, average, and 95th percentile Reliability Signposting Graphical “C” G. Graphical “D”
H.
Auditory “B”
A. B. C. D. E.
78
Experiment Implementation
Pre-experiment survey, commuting game, and mini post-experiment survey for Exp#1 users Often experiment completed within 60-70 minutes in Washington DC, while we ‘had’ participants for 90 minutes. Consequently, paper survey added in Chicago and Houston requests participants rank six of seven types of info (auditory was excluded)
Expanded Experiment Design
Reliability Data Content
#1 Two Distinct Experiments: 5 cities, 1 week each city* Implementation Version Planned Participant Count Valid "good" Participant Count A. Control (no reliability info) B. C. D. E. F. G. H.
Textual 95TH Textual Avg + 95TH Textual 20TH+ Avg + 95TH Visual and Textual signposting Graphical presentation of "C" Graphical presentation of "D" Auditory presentation of "B"
1 90 98 P P P P P
2 30 29 P P P P P
3 30 25 P P P
#2 1 city*, 4 wks.
4 30 33 P
5 30 30 P
6 30 30
P P
P P
P P
P
*city refers to travel in simulated city for participants and not city of experiment implementation
80
Participant Characteristics
More educated sample than population at large Older sample population than population at large Definition of Late Arrival
81
Exp#1 Schedule Offset Costs
Schedule offset savings are statistically and practically significant for simpler forms of reliability information
*lighter shades are not statistically significant
No Reliability Info Reliability Info 82
Exp#1 Late Arrival Frequency
When offered simpler forms of reliability information, participants were late less often
*lighter shades are not statistically significant
No Reliability Info Reliability Info 83
Exp#1 Perceived Benefits
End-of-week difference in willingness to pay often not statistically significant between trips with and without reliability information End-of-week usefulness higher for ‘simple’ reliability information but not for ‘complex’ reliability data. Post-trip usefulness and stressfulness levels often not statistically significant or lower for reliability terms
84
Exp#1 Comparing Delivery Media
Text v. Auditory 95th Percentile Info Generally
no statistically significant differences for trip outcomes or valuation Text rated slightly more difficult to understand compard 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 85
Exp#1 Comparing Delivery Media
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.
86
Exp#2 Late Arrival Frequency
Benefits of reliability info decrease over time Participants using reliability info perform on week 1 as well as their counterparts at week 4
87
Exp#1 Post Survey Survey replies on reliability info usefulness and complexity mirrors what is observed in the experiment. Benefits reflects difference between usefulness and complexity. 88
Paper Post-Experiment Survey Different ratings from paper survey on the usefulness of reliability information compared to the quantified valuation observed in the first experiment. Complex graphic rated equivalent to text 95th with regard to usefulness. 89
Findings – Hypothesis #1 1. Provision of reliability information does improves ontime performance versus a control group that receives no reliability information a. Some forms are more effective than others Provision of simple forms of reliability information had similar results whether provided in text, graphic or auditory forms. More complex graphical & signposting concepts not effective. b. Perceived benefit do trail actual benefit Perceived benefits unclear in presence of quantitative benefits.
Findings – Hypothesis #2 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.
Findings – Hypothesis #3
The provision of reliability signposts in real-time information does not improve on-time performance The
signposting concept was not successful for participants in the management of trip outcomes and stress reduction. To some degree, this was because of the complexity of the presentation and the brevity with which participants were required to learn and interpret information content.
92
Potential Future Research Directions
Reliability information in the context of more complex multi-modal trip, trip chain and tour planning. Impact of reliability information on broader range of travel-related choices. Mechanisms of reliability information under-valuation by users.
93
Part 3: Discussion and Comments on Deliverables Beverly Kuhn, TTI
Lexicon
Phrase book to be used across platforms. Potential uses. Public
outreach. Performance measure reports. TMC pre-trip planning websites. Commercial traffic routing systems.
95
Guidebook Chapters
1 – Introduction 2 – The Concept of Travel Time Reliability 3 – Key Messages 4 – Relevant Travel Time Reliability Terms 5 – Methods of Communicating Travel Time Reliability 6 – Measuring Information Effectiveness 7 – Emerging Trends 8 – Final Remarks 9 – References 96
Lexicon Terminology
95th Percentile Arrival Time Average Travel Time Buffer Time Departure Time Recommended Departure Time Recommended Route Reliability 97
Lexicon –
th 95
Percentile
Technical Term 95th Percentile Definition The point on a travel time frequency distribution at which 95% of the trips made would be at or less than the identified time. Usage To describe the longest time a driver can expect a trip to take. Information Technology Platforms Recommendation
Alternate Phrase
Majority of the time Best
Wording Context / Additional Information “The majority of the time, your trip will take X minutes or less.” MAJORITY OF TIME TRIP TO [DESTINATION] X MIN OR LESS Graphical representation of the average + 95th percentile.
Most of the time
Adequate Travel time for planning
95th percentile trip time
Avoid
Maximum trip time Most common trip time Worst case trip time
“Most of the time, your trip will take X minutes or less.” MOST OF THE TIME TRIP TO [DESTINATION] X MIN OR LESS “Travel time for planning is X minutes or less.” “The 95th percentile trip time is X minutes or less.” Provide description such as “19 out of 20 days”. Agency concerns regarding liability and credibility.
Web
Mobile Web
Dynamic Message Sign
Text
Mobile Application
√
√
X
√+
√+
√
√
√>
√
√
√
√
X
X
√
√
√
X
√+
√+
√
√
√>
√
√
√
√
X
√+
√+
√
√
X
√+
√+
N/A
N/A
N/A
N/A
98N/A
Lexicon – Arrival Time Technical Term Definition Usage
Arrival Time The time at which a traveler would arrive after a trip. To tell the driver when they can expect to arrive at their destination.
99 Recommendation
Best
Alternate Phrase
Arrive by Arrive at
What time do you want to get there?
Adequate
What’s the earliest you can arrive
What’s the latest you can arrive?
Wording Context / Additional Information “Arrive by X:XX am / pm.” ARRIVE BY X:XX AM/PM “Arrive at X:XX am / pm.” ARRIVE AT X:XX AM/PM This question would be used by a traveler to enter a preferred arrival time into a travel time calculator to receive a recommended departure time. This question would be used by a traveler to enter a preferred arrival time into a travel time calculator to receive a recommended departure time. This question would be used by a traveler to enter a preferred arrival time into a travel time calculator to receive a recommended departure time.
Information Technology Platforms Dynam Mobile Mobile ic Applica Web Text Messag Web tion e Sign √ √ X √ √ √ √ √>% √ √ √ √ X √ √ √ √ √>% √ √
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X
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Avoid
99
10 0
Lexicon – Average Travel Time Technical Term Average Travel Time Definition An average of historical travel times calculated over a specified time interval for a specified trip or roadway segment. Usage To describe the typical travel time a driver can expect a trip will take. Information Technology Platforms Recommendation
Alternate Phrase
Wording Context / Additional Information
Web
Mobile Web
Dynamic Message Sign
Text
Mobile Application
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“Typical travel time is X minutes.”
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X
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Graphical representation of the average + 95th percentile (typical day and bad day).
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Graphical representation of the 20th percentile + average + 95th percentile (good, typical, and bad day).
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“Average travel time is X minutes.”
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“Expected travel time is X minutes.”
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Difficult to determine relevance with no comparison to real-time information.
N/A
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“Estimated travel time is X minutes.” Estimated travel time Best
Approximate travel time Typical travel time
Adequate
Average travel time Expected travel time
Avoid
Historical Travel Time
“It is estimated that your trip will take X minutes.” EST THAT TRIP TO [DESTINATION] WILL TAKE X MIN “It will take approximately X minutes to make your trip.” APPROX X MIN TO [DESTINATION]
100 N/A
10 1
Lexicon – Buffer Time Technical Term Definition Usage
Buffer Time The average travel time multiplied by the buffer index. To describe how much extra time a driver should plan for a trip they wish to take. Information Technology Platforms
Recommendation
Alternate Phrase
Best
Extra time
Web
Mobile Web
Dynamic Message Sign
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Mobile Application
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“Recommended cushion for trip is X minutes.”
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Preference shown for other terms.
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Wording Context / Additional Information
“Extra time for trip is X minutes.” Extra time to [destination] is X min “Added time for trip is X minutes.”
Added time Adequate
Avoid
Recommended cushion Cushion
Added time to [destination] is X min
101
10 2
Lexicon – Departure Time Technical Term Departure Time Definition The time at which a traveler would depart for a trip. Usage To indicate the time a traveler departs for a trip. For DMS applications, message would need to be set in context with other information, such as destination, travel time, or route.
Recommendation
Best
Adequate
Alternate Phrase Departing at Leave at What time will you start your trip?
Leave by Departing by What’s the earliest you can start your trip?
What’s the latest you can start your trip?
Wording Context / Additional Information “Departing at X:XX am / pm.” “Leave at X:XX am / pm.” This question would be used by a traveler to enter a start time into a travel time calculator to receive an arrival time. “Leave by X:XX am / pm.” “Departing by X:XX am / pm.” This question would be used by a traveler to enter a start time into a travel time calculator to receive an arrival time. This question would be used by a traveler to enter a start time into a travel time calculator to receive an arrival time.
Web √ √
Information Technology Platforms Dynamic Mobile Mobile Message Text Web Application Sign √ X √ √ √ X √ √
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X X
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Avoid
102
10 3
Lexicon – Recommended Departure Time Technical Term Recommended Departure Time Definition A time of departure displayed to a traveler which is calculated by a traveler information system and would ensure an ontime arrival for a given level of added delay. Usage To indicate the time a driver should depart for a trip to ensure they arrive at their destination on time. For DMS applications, would need to be set in context with other information, such as destination, travel time, or route.
Recommendation
Best
Adequate
Alternate Phrase
Wording Context / Additional Information
Recommended departure “Recommended departure time is time X:XX am / pm.” Suggested departure time “Suggested departure time is X:XX am / pm.” Estimated departure “Estimated departure time is X:XX time> am / pm.” >> “The 95th percentile departure th 95 percentile departure time is X:XX am / pm.” Provide description such as “19 time out of 20 days”.
Web
Information Technology Platforms Dynamic Mobile Mobile Message Text Web Application Sign
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Avoid
103
10 4
Lexicon – Recommended Route Technical Term Recommended Route Definition A route between two points calculated by a traveler information system which would provide the best probability of on-time arrival to a specific destination. Usage To describe the route a driver should take for a planned trip to ensure he/she arrives on time to his/her destination.
Recommendation
Best
Alternate Phrase
Best route Forecasted trip
Most reliable trip
Adequate
Most predictable trip
Most consistent trip
Wording Context / Additional Information
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X
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MOST PREDICTABLE TRAVEL TIME TO [DESTINATION] TAKE [FACILITY]
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“Most consistent trip is via [facility].”
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“Best route is via [facility].” BEST ROUTE TO [DESTINATION] TAKE [FACILITY] “Forecasted trip is via [facility].” FORECASTED TRIP TIME VIA [FACILITY] X MIN “Most reliable trip is via [facility].” MOST RELIABLE TRAVEL TIME TO [DESTINATION] TAKE [FACILITY] “Most predictable trip is via [facility].”
MOST CONSISTENT TRAVEL TIME TO [DESTINATION] TAKE [FACILITY]
Avoid
Historical trip conditions Least variable time
Web
Information Technology Platforms Dynamic Mobile Mobile Message Text Web Application Sign
Difficult to determine relevance with no comparison to real-time information. Preference shown for other terms.
104 N/A
10 5
Lexicon – Reliability Technical Term Reliability Definition A consistency or dependability in travel times between two points, as measured from day to day or across different times of day. Usage To describe the variability of travel times to drivers so they can plan their trip with more robust information.
Recommendation
Alternate Phrase
Best
Predictable Reliable Consistent Vary Differ Fluctuate Change Go up or down Increase or decrease Deviate
Adequate
Avoid
Wording Context / Additional Information
Web
“Most predictable trip” “Most reliable trip.” “Most consistent trip.” “Trip varies.”
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Preference shown for other terms.
N/A
Information Technology Platforms Dynamic Mobile Mobile Message Text Web Application Sign √ X √ √ √ X √ √ √ X √ √ √ X √ √
N/A
N/A
N/A
N/A
105
Lexicon Not Provided
Buffer Index Not tested in the human factors studies. Metric unlikely to be used by roadway users.
Delay Time Not tested in human factors studies. Terms tested for the related concept “buffer time”.
Free Flow Travel Time Not tested in focus groups or surveys. Phrase “great day” used in enhanced laboratory study along with corresponding “typical” and “bad” days.
106
Lexicon Not Provided
Peak Travel Time Not tested in the human factors studies. Terms tested for similar concept “95th percentile travel time”.
Planning Time Not tested in the human factors studies. Terms tested for similar concept “95th percentile travel time”. “Travel time for planning” was one of the alternatives tested to represent 95th percentile travel time.
Planning Time Index Not tested in the human factors studies. Metric unlikely to be used by roadway users.
107
Lexicon Not Provided
Total Trip Time Not tested in human factors studies. A commonly-used phrase and few synonyms exist.
Travel Time Savings Not tested in human factors studies. A commonly-used phrase and few synonyms exist.
Travel Time Range
In computer survey, subjects more often felt a single trip time (typical/avg or 95th percentile) was reliable when compared to a travel time range.
Trend Information
Not tested in human factors studies. 108
Final Report
1 – Introduction 2 – Literature Review 3 – Expert Interviews 4 – Technology and Innovation Scan 5 – Develop Avenues of Investigation 6 – Focus Groups 7 – Usability Surveys
8 – Travel Behavior Laboratory Experiment 9 – Enhanced Laboratory Experiment 10 – Lexicon Development 11 – Final Remarks 12 – References
109
Part 4: Next Steps Beverly Kuhn, TTI Karl Wunderlich, Noblis
Project Timeline
Project Closeout Meeting with TETG
Sep 26, 2012
Discuss comments on Draft Guidebook & Deployment Advisory
Discuss comments on Final Report
Address TETG Comments & Submit Final Documents
Draft Guidebook & Deployment Advisory
Final Report
Oct 15, 2012
Review Process
Oct-Jan 2013
Project Conclusion
Jan 31, 2013
111
Product Review Process
112
Publication Issues
113
Implementation
How can the main outcome of this project – the Guidebook and Deployment Advisory – be used by an operating agency? Who are the potential first users?
114
Questions Beverly Kuhn, TTI [email protected] 979-862-3558 Karl Wunderlich, Noblis [email protected] 202-488-5707 Vaishali Shah, Noblis [email protected] 202-488-5715 115
