DOI: 10.5061/dryad.g79cnp62m
title: Data from: Data collection of Odometer images via WhatsApp to measure vehicle miles traveled report

description: This dataset contains relevant information used in the study of collecting
 odometer images via WhatsApp to measure vehicle miles traveled (VMT) in
 California. In recent years, policymakers have increasingly suggested
 interventions for sustainable transportation, directly or indirectly
 aiming to reduce vehicle miles traveled. Researchers in transportation
 have used various ways to collect VMT data for their analysis, but there
 are pros and cons to each method. Self-reported VMTs from travel surveys
 are traditionally used to understand factors affecting VMT or estimate
 policy effects, yet such data suffer from recall error, rounding, and
 heaping biases in reporting numbers by which researchers derive VMT.
 Surveys with the latest technologies, such as a dedicated GPS device, can
 provide more accurate VMT but can be intrusive on participants’ privacy
 and too expensive to scale. Passively collected data, such as traffic
 counts or states’ odometer reading data, rarely capture travelers’
 characteristics, limiting the capability of travel behavior analysis. In
 this study, we developed a new VMT data collection method using WhatsApp
 through three tasks: 1) a comprehensive literature review of the data
 collection methods for VMT-related arguments, assessing their strengths
 and shortcomings; 2) the development of an automation system to collect
 odometer images from participants via WhatsApp, and 3) a pilot deployment
 of a real-world study and evaluation of the results, with a discussion of
 circumstances that this method could provide benefits compared to other
 existing approaches and of limitations or challenges. The results will
 provide guidelines to planners, policymakers, and researchers in choosing
 and implementing strategies for VMT data collection, including those
 presented here, depending on their analysis and practical needs.
description: # Dataset of "Data Collection of Odometer Images via WhatsApp to
 Measure Vehicle Miles Traveled" Dataset DOI:
 [10.5061/dryad.g79cnp62m](10.5061/dryad.g79cnp62m) ## Description of the
 data and file structure This dataset contains relevant information used in
 the study "Data collection of Odometer images via WhatsApp to measure
 vehicle miles traveled", an NCST-supported project conducted by the
 Institute of Transportation Studies, UC Davis. This repository contains
 three files: 1. posts_pii_removed.csv 2. survey_pii_removed.csv 3.
 users_pii_removed.csv These files represent the odometer images collected
 during the study, data of the prescreening survey, and the user
 statistics, respectively, with all personal identifiable information
 removed. ### Files and variables #### File: posts_pii_removed.csv
 **Description:** This data contains information about the posts (odometer
 images submitted during the study). ##### Variables * id: ID. String. *
 image_create_date: The datetime when the image was submitted. String in
 the "YYYY-MM-DDTHH:mm:ss.SSS[Z]" format in UTC. * vmt: The value
 of the vehicle miles traveled. Integer.  * status: The status of the post.
 String. * is_deleted: Indicator of whether the image binary has been
 deleted by the user. Boolean. * posted_by_id: The id of the user who
 posted this image. String. * notes: Any notes added by the admin. String.
 * image_size: The image size in bytes. Integer. * visible: Indicator of
 whether the image was visible on the frontend UI. Boolean. #### File:
 survey_pii_removed.csv **Description:** This data contains information
 about the prescreening survey. ##### Variables * StartDate: The datetime
 when the survey participant started the survey. String in the format of
 "YYYY-MM-DD" in US Mountain Time. * EndDate: The datetime when
 the survey participant ended the survey. String in the format of
 "YYYY-MM-DD" in US Mountain Time. * Status: The status of the
 survey response. Integer. * Progress: The progress of the survey response,
 assuming that 100 is completed. Integer. * Duration__in_seconds_: Time
 taken to complete the survey. Integer in seconds.  * Finished: Indicator
 of whether the survey response is completed or not. Integer. *
 RecordedDate: The datetime when the survey response is recorded. String in
 the format of "YYYY-MM-DD HH:mm:ss" in US Mountain Time. *
 ResponseId: ID. String. * ExternalReference: Referencial ID. String *
 DistributionChannel: The distribution of the survey by which the response
 was made. String. * UserLanguage: The language used in the survey. String.
 * Q2: The gender identity of the participant. 1="Woman",
 2="Man", 3="Prefer to self-describe". * Q2_3_TEXT: The
 gender identity details if the participant selected 3 in Q2. String. * Q3:
 The household income level of the participant, in USD. 1="Less than
 $50,000", 2="$50,000 to $99,999", 3="$100,000 to
 $149,999", 6="$150,000 or more", 5= "Prefer not to
 answer". * Q4: The educational attainment of the
 participant. 1="Some grade/high school", 2="Completed high
 school or GED", 3="Some college/technical school",
 4="Bachelor’s degree(s)", 5="Graduate degree(s) (e.g., MS,
 PhD, MBA)", 6="Professional degree(s) (e.g., JD, MD, DDS)",
 7="Prefer not to answer". * Q5: The possession of the
 driver's license of the participant. 1="Yes",
 2="No" * Q6_1: The number of the household vehicles that the
 participant's household possesses. Integer. * Q8_1: The number of the
 people who would drive the vehicle that the participant would report the
 VMT for. Integer.  * Q9_6: An estimate of the VMT that the vehicle made in
 the last seven days. Integer. * Q10_1: The confidence in the estimate made
 in Q9_6. 1="It’s very hard to recall it", 2="I struggled a
 bit to estimate it", 3="I think I remembered it okay",
 4="I’m pretty sure I got it right", 5="Yes, I remember it
 exactly". * Q11_1: An estimate of the VMT that the vehicle would make
 today, counting from the date when the participant took the survey.
 Integer. * Q11_2: An estimate of the VMT that the vehicle would make one
 day later, counting from the date when the participant took the survey.
 Integer. * Q11_3: An estimate of the VMT that the vehicle would make two
 day later, counting from the date when the participant took the survey.
 Integer. * Q11_4: An estimate of the VMT that the vehicle would make three
 day later, counting from the date when the participant took the survey.
 Integer. * Q11_5: An estimate of the VMT that the vehicle would make four
 day later, counting from the date when the participant took the survey.
 Integer. * Q11_6: An estimate of the VMT that the vehicle would make five
 day later, counting from the date when the participant took the survey.
 Integer. * Q11_7: An estimate of the VMT that the vehicle would make six
 day later, counting from the date when the participant took the survey.
 Integer. * Q12_1: The confidence in the estimate made in Q11_1 to
 Q11_7. 1="Not confident at all", 2="Slightly
 confident", 3="Moderately confident", 4="Very
 confident", 5="Completely confident". * age: Categorized
 age (for deidentification purpose) that falls into one of "Under
 25", "25-39", or "40 or more". #### File:
 users_pii_removed.csv **Description:** This data contains information
 about the users of the study. ##### Variables * id: ID. String in the UUID
 (v4) format. * createdAt: The datetime when the user data was created on
 the database. String in the "YYYY-MM-DD" format in UTC. *
 updatedAt: The datetime when the user data was last updated on the
 database. String in the "YYYY-MM-DD" format in UTC. *
 activatedAt: The datetime when the user registered to the study by using
 the access code. String in the "YYYY-MM-DD" format in UTC. *
 deletedAt: The datetime when the user deleted their account for the study.
 String in the "YYYY-MM-DD" format in UTC. * accessCode: The
 unique access code used for registration and deletion of the account.
 String. * userStatusId: The status of the user. String. * invitations: Not
 used (a referential variable for another database table). * posts: Not
 used (a referential variable for another database table). *
 lastInvitationSentAt: The datetime when the last instruction email was
 sent to the user. Note that some rows has null value due to issues in a
 security update of the university email address. String in the
 "YYYY-MM-DD HH:mm:ss.SSS" format in UTC. * invitationCount: The
 number of instruction emails sent to the user. Integer. * postCount: The
 number of posts that the user submitted. Integer. * submittedPostCount:
 The number of posts that the user submitted and not processed by the admin
 or user afterwards. Integer. * readPostCount: The number of posts that the
 user submitted and the admin added the odometer reading to it, yet not
 approved. Integer. * approvedPostCount: The number of posts that the user
 submitted and the admin approved. Integer. * rejectedPostCount: The number
 of posts that the user submitted and the admin rejected. Integer. *
 deletedPostCount: The number of posts that the user submitted but later
 deleted. Integer. * visible: Indicator of whether the image was visible on
 the frontend UI. Boolean. ## Code/software Text viewer or Microsoft Excel
 can open the files. ## Human subjects data For the "survey"
 subdataset, we applied a grouping of the age of the study participants.
 For the "users" subdataset, we removed the exact time of the
 day.